Process for dyeing keratin fibres using at least one particular triarylmethane dye and at least one fluorescent dye

ABSTRACT

The present invention also relates to the use of said dyes for dyeing light keratin fibres, especially human keratin fibres such as the hair, in chestnut-brown, dark chestnut-brown, brown, brown with a glint, or even black, without using an additional dye other than those defined above.

The present invention relates to a process for dyeing keratin fibres, inparticular human keratin fibres such as the hair, using one or moreparticular triarylmethane dyes and one or more fluorescent dyes.

The present invention also relates to a cosmetic composition comprisingthe dyes defined above, and also to a multi-compartment devicecontaining said dyes.

The present invention also relates to the use of said dyes for dyeinglight keratin fibres, especially human keratin fibres such as the hair,in chestnut-brown, dark chestnut-brown, brown, brown with a glint, oreven black, without using an additional dye other than those definedabove.

Many people have sought for a long time to modify the colour of theirhair and in particular to mask their grey hair.

It is especially known practice to dye keratin fibres, in particularhuman keratin fibres, with dye compositions containing oxidation dyeprecursors, which are generally known as oxidation bases. Theseoxidation bases are colourless or weakly coloured compounds, which, whencombined with oxidizing products, may give rise to coloured compoundsvia a process of oxidative condensation.

The shades obtained with these oxidation bases may be modified bycombining them with couplers or colour modifiers. The variety ofmolecules used as oxidation bases and couplers allows a wide range ofcolours to be obtained.

Another well-known method consists in obtaining semi-permanent dyeing byapplying to the keratin fibres direct dyes, which are coloured andcolouring molecules that have affinity for said fibres.

The direct dyes conventionally used are chosen from nitrobenzene,anthraquinone, nitropyridine, azo, xanthene, acridine, azine andtriarylmethane direct dyes. The chemical species may be nonionic,anionic (acidic dyes) or cationic (basic dyes). The direct dyes may alsobe natural dyes.

Conventional direct dyeing processes consist in applying to keratinfibres dye compositions comprising direct dyes. After application, aleave-on time is observed so as to allow the dye molecules to penetrateby diffusion into the fibres. On conclusion of the process, the fibresare rinsed.

In contrast with oxidation dyeing, these direct dyeing processes have atendency to better protect the integrity of the fibres. The resultingcolourings are generally chromatic, but, however, are onlysemi-temporary. The nature of the interactions that bind the direct dyesto the keratin fibres and their desorption from the surface and/or thecore of the fibre are responsible for their weak dyeing power.

Although a wide range of colours is currently accessible, it generallyproves necessary to combine three dyes of complementarycolours—trichromatic principle—in order to obtain a natural shade (see,for example, WO 95/15144 and WO 95/01772). This tripartite combinationdoes not, however, show good persistence with respect to repeatedshampooing. It generally, or even systematically, induces an unaestheticchanging of the colour, which the consumer finds dissuasive.

These colourings are furthermore not sufficiently fast in the face ofexternal agents such as light or perspiration.

Thus, there is a real need to implement processes for the direct dyeingof keratin fibres, in particular of human keratin fibres such as thehair, which do not have the drawbacks mentioned above, i.e. which makeit possible especially to lead to natural colourings that have goodproperties, especially in terms of chromaticity, power, intensity, sheenand selectivity, and which are persistent with respect to shampooing.

Another aim of the present invention is thus to be able to dye lightkeratin fibres efficiently in chestnut-brown, dark chestnut-brown, brownor brown with a glint or even black, by mixing direct dyes, andpreferably only two types of direct dye.

The Applicant has found, surprisingly, that a process for dyeing keratinfibres using one or more particular triarylmethane dyes and one or morespecific fluorescent dyes makes it possible to achieve the objectivesmentioned above; especially to lead to natural chestnut-brown, darkchestnut-brown, brown, brown with a glint or even black colourings,which are not only powerful and shiny, but also shampoo-resistant.

One subject of the present invention is especially a process for dyeingkeratin fibres, in particular human keratin fibres such as the hair,comprising the application to said keratin fibres of the followingingredients:

(a) one or more triarylmethane dyes chosen from the compounds of formula(I) below, the optical isomers thereof, the geometrical isomers thereof,the tautomers thereof, the organic or mineral, acid or base saltsthereof, the solvates thereof such as hydrates, and mixtures thereof,

in which formula (I):

-   -   R₁, R₂, R′₁ and R₂, which may be identical or different,        represent:        -   a hydrogen atom,        -   a linear or branched C₁ to C₂₀ alkyl radical;            -   that is optionally substituted and/or            -   optionally interrupted with one or more heteroatoms,                preferably oxygen or sulfur, and/or with one or more                groups comprising at least one heteroatom, preferably                chosen from oxygen, sulfur, C(O), SO, SO₂ and SO₃ ⁻, or                combinations thereof, or        -   a benzyl radical optionally substituted with one or more SO₃            ⁻ or SO₃H groups;    -   R₃ and R′₃, which may be identical or different, represent,        independently of each other:        -   a linear or branched C₁ to C₆ alkyl radical;        -   a sulfonate group SO₃ ⁻, or        -   a sulfonic group SO₃H;    -   n and m, which may be identical or different, represent two        integers ranging from 0 to 4;    -   the radicals R₄, which may be identical or different, represent,        independently of each other:        -   a linear or branched C₁ to C₆ alkyl radical;        -   a hydroxyl radical,        -   a group SO₃ ⁻,        -   a group SO₃H,        -   a halogen atom, preferably a chlorine atom,        -   or alternatively two adjacent radicals R₄ together form an            unsaturated 6-membered ring, preferably an aromatic ring            such as benzo, optionally substituted with one or more SO₃ ⁻            or SO₃H groups;    -   q is an integer ranging from 0 to 4;    -   R₅ represents:        -   a hydrogen atom,        -   a halogen atom, preferably a chlorine atom,        -   an amino radical,        -   a hydroxyl radical,        -   a group which is electron-withdrawing via the mesomeric            effect, such as SO₃ ⁻ or SO₃H, or        -   a radical —NR₆R₇, in which R₆ and R₇, which may be identical            or different, represent, independently of each other:            -   a hydrogen atom,            -   a linear or branched C₁ to C₆ alkyl radical;    -   it being understood that:        -   the radical R₂ is present or absent, symbolized by the            dashed bond, when R₂ is present, then the nitrogen atom that            bears it is in cationic ammonium form, when R₂ is absent,            then the nitrogen atom that bears it is not charged, (+) is            not present, and        -   the compound of formula (I) optionally comprises one or more            anions An⁻ and optionally one or more cations M⁺ to ensure            the electrical neutrality of the molecule;    -   with:        -   An⁻ representing an anion, preferably chosen from bromide,            chloride, methylsulfate and toluenesulfonate ions or a            mixture of these ions; and        -   M⁺ representing a cation, preferably chosen from sodium,            potassium, magnesium, calcium, zinc and ammonium ions or a            mixture of these ions; and            (b) one or more fluorescent dyes; said fluorescent dyes            being direct dyes chosen from cyanin dyes, styryl/hemicyanin            dyes, naphthalimide dyes, and mixtures thereof; it being            understood that the triarylmethane dye(s) (a) and the            fluorescent dye(s) (b) are applied to said keratin fibres            together or sequentially.

Another subject of the invention is a cosmetic composition comprising:

(a) one or more triarylmethane dyes chosen from the compounds of formula(I), as defined previously, and also the optical isomers thereof, thegeometrical isomers thereof, the tautomers thereof, the organic ormineral acid or base salts thereof, the solvates thereof such ashydrates, and mixtures thereof; and(b) one or more fluorescent dyes, as defined previously.

The combination of particular triarylmethane dye(s) and of fluorescentdye(s) makes it possible especially to obtain natural colourings thathave good dyeing properties, especially in terms of chromaticity, power,intensity, sheen and selectivity.

Furthermore, the process and the composition according to the inventionmake it possible to dye light keratin materials efficiently inchestnut-brown, dark chestnut-brown, brown, brown with a glint or evenblack, by mixing direct dyes, and in particular only the dyes (a) and(b) as defined previously, without the need to use an additional (orcomplementary) dye other than (a) or (b).

Moreover, the colourings obtained by means of the process and thecomposition according to the invention show good resistance to thevarious attacking factors to which the hair may be subjected, such aslight, bad weather, washing and perspiration. They are in particularpersistent with respect to shampooing, especially after at least threeshampoo washes.

A subject of the present invention is also a multi-compartment devicecomprising a first compartment containing one or more triarylmethanedyes (a) chosen from the compounds of formula (I) as defined previously,and also the optical isomers thereof, the geometrical isomers thereof,the tautomers thereof, the organic or mineral acid or base saltsthereof, the solvates thereof such as hydrates, and mixtures thereof,and a second compartment containing one or more fluorescent dyes (b) asdefined previously.

Another subject of the invention is the use of fluorescent dye(s), asdefined previously, combined with triarylmethane dye(s) chosen from thecompounds of formula (I), as defined previously, and also the opticalisomers thereof, the geometrical isomers thereof, the tautomers thereof,the organic or mineral acid or base salts thereof, the solvates thereofsuch as hydrates, and mixtures thereof, for the dyeing of light keratinfibres, especially human keratin fibres such as the hair, inchestnut-brown, dark chestnut-brown, brown, brown with a glint or evenblack, without using an additional dye other than (a) or (b).

Other subjects, characteristics, aspects and advantages of the inventionwill emerge even more clearly on reading the description and theexamples that follow.

For the purposes of the present invention and unless otherwiseindicated:

-   -   the “dyes” according to the invention absorb light in the        visible range, i.e. at a wavelength λ_(abs) particularly between        400 and 700 nm inclusive;    -   for the purposes of the present invention, the term “direct dye”        means natural and/or synthetic dyes, which are soluble in the        cosmetic medium, other than oxidation dyes; they are dyes which        will diffuse superficially on the keratin fibres;    -   for the purposes of the present invention, the term “fluorescent        dye” means a dye which is a coloured molecule (which absorbs        visible light) and which itself imparts colour, and which, in        contrast with a conventional dye, transforms the absorbed energy        into light of a longer wavelength emitted in the visible part of        the spectrum; in particular, the “fluorescent” dyes of the        invention are capable of absorbing light in the visible range at        a wavelength λ_(abs) of between 350 and 800 nm and of        re-emitting in the visible range at a longer wavelength λ_(em)        than that absorbed, of between 400 and 800 nm; the difference        between the absorption and emission wavelengths, also known as        the Stoke's shift, is between 1 nm and 100 nm. More        preferentially, the fluorescent dyes of the invention are dyes        that are capable of absorbing at a wavelength λ_(abs) of between        420 nm and 550 nm and of re-emitting in the visible range at a        wavelength λ_(em) of between 470 and 600 nm;    -   the “fluorescent dyes” according to the present invention are to        be differentiated from optical brighteners. Optical brighteners,        also generally known as “brighteners” or “fluorescent        brighteners” or “fluorescent brightening agents” or “fluorescent        whitening agents or FWA” or “whiteners” or “fluorescent        whiteners”, are colourless compounds, which do not impart a        colour and are consequently not dyes since they do not absorb in        the visible light range, but only absorb in the ultraviolet        range (wavelength ranging from 200 to 400 nm) and transform the        absorbed energy into fluorescent light of a longer wavelength        emitted in the visible part of the spectrum in the blue range.        The colour impression is then generated only by the purely        fluorescent light that is predominantly blue (wavelength ranging        from 400 to 500 nm).    -   the “blue-violet” dyes according to the invention are dyes which        absorb light in the visible spectrum and which appear blue        visually, i.e. which absorb light at an absorption wavelength        λ_(max) greater than 550 nm and less than or equal to 700 nm, in        particular λ_(max) between 560 nm and 700 nm, preferably in the        blue range, i.e. λ_(max) between 580 and 650 nm    -   the term “(hetero)aryl” means aryl and heteroaryl groups;    -   the “aryl” or “heteroaryl” radicals or the aryl or heteroaryl        part of a radical may be substituted with at least one        substituent borne by a carbon atom, chosen from:        -   a C₁-C₆ and preferably C₁-C₄ alkyl radical optionally            substituted with one or more radicals chosen from hydroxyl,            C₁-C₂ alkoxy, C₂-C₄ (poly)hydroxyalkoxy, acylamino, amino            substituted with two C₁-C₄ alkyl radicals, which may be            identical or different, optionally bearing at least one            hydroxyl group, or the two radicals possibly forming, with            the nitrogen atom to which they are attached, a saturated or            unsaturated, optionally substituted 5- to 7-membered and            preferably 5- or 6-membered heterocycle optionally            comprising another nitrogen or non-nitrogen heteroatom;        -   a halogen atom such as chlorine;        -   a hydroxyl or thiol group;        -   a C₁-C₆ alkoxy or C₁-C₆ alkylthio radical;        -   a (poly)hydroxy(C₂-C₆)alkoxy radical;        -   an amino radical;        -   a 5- or 6-membered heterocycloalkyl radical, preferentially            morpholino, piperazino, piperidino or pyrolidino, which is            optionally substituted with a (C₁-C₄) alkyl radical,            preferentially methyl;        -   a 5- or 6-membered heteroaryl radical, preferentially            imidazolyl, optionally substituted with a (C₁-C₄)alkyl            radical, preferentially methyl;        -   an amino radical substituted with one or two identical or            different C₁-C₆ alkyl radicals, optionally bearing at least:            -   i) a hydroxyl group,            -   ii) an amino group optionally substituted with one or                two optionally substituted C₁-C₃ alkyl radicals, said                alkyl radicals possibly forming with the nitrogen atom                to which they are attached a saturated or unsaturated,                optionally substituted 5- to 7-membered heterocycle,                optionally comprising at least one other nitrogen or                non-nitrogen heteroatom,            -   iii) a quaternary ammonium group —N⁺R′R″R′″, M⁻ for                which R′, R″ and R′″, which may be identical or                different, represent a C₁-C₄ alkyl group and M⁻                represents an anionic counterion,            -   iv) or an optionally cationic 5- or 6-membered                heteroaryl radical, preferentially imidazolium,                optionally substituted with a (C₁-C₄)alkyl radical,                preferentially methyl;        -   an acylamino radical (—N(R)—C(O)—R′) in which the R radical            is a hydrogen atom or a C₁-C₄ alkyl radical optionally            bearing at least one hydroxyl group and the R′ radical is a            C₁-C₂ alkyl radical;        -   a carbamoyl radical ((R)₂N—C(O)—) in which the R radicals,            which may be identical or different, represent a hydrogen            atom or a C₁-C₄ alkyl radical optionally bearing at least            one hydroxyl group;            -   an alkylsulfonylamino radical (R′—S(O)₂—N(R)—) in which                the R radical represents a hydrogen atom or a C₁-C₄                alkyl radical optionally bearing at least one hydroxyl                group and the R′ radical represents a C₁-C₄ alkyl                radical, or a phenyl radical;            -   an aminosulfonyl radical ((R)₂N—S(O)₂—) in which the R                radicals, which may be identical or different, represent                a hydrogen atom or a C₁-C₄ alkyl radical optionally                bearing at least one hydroxyl group;            -   a carboxyl radical in the acid or salified form                (preferably salified with an alkali metal or a                substituted or unsubstituted ammonium);            -   a cyano group;            -   a nitro or nitroso group;            -   a polyhaloalkyl group, preferably trifluoromethyl;        -   the cyclic or heterocyclic part of a non-aromatic radical            may be substituted with at least one substituent chosen from            the following groups:            -   hydroxyl;            -   C₁-C₄ alkoxy, C₂-C₄ (poly)hydroxyalkoxy;            -   C₁-C₄ alkyl;            -   alkylcarbonylamino (R—C(O)—N(R′)—) in which the radical                R′ is a hydrogen atom or a C₁-C₄ alkyl radical                optionally bearing at least one hydroxyl group, and the                radical R is a C₁-C₂ alkyl radical or an amino radical                optionally substituted with one or two C₁-C₄ alkyl                groups, which may be identical or different, themselves                optionally bearing at least one hydroxyl group, said                alkyl radicals possibly forming, with the nitrogen atom                to which they are attached, a saturated or unsaturated,                optionally substituted 5- to 7-membered heterocycle                optionally comprising at least one other nitrogen or                non-nitrogen heteroatom;            -   alkylcarbonyloxy (R—C(O)—O—) in which the radical R is a                C₁-C₄ alkyl radical or an amino group optionally                substituted with one or two identical or different C₁-C₄                alkyl groups themselves optionally bearing at least one                hydroxyl group, said alkyl radicals possibly forming                with the nitrogen atom to which they are attached a                saturated or unsaturated, optionally substituted 5- to                7-membered heterocycle, optionally comprising at least                one other nitrogen or non-nitrogen heteroatom;            -   alkoxycarbonyl (R—X—C(O)—) in which the radical R is a                C₁-C₄ alkoxy radical, X is an oxygen atom or an amino                group optionally substituted with a C₁-C₄ alkyl group                itself optionally bearing at least one hydroxyl group,                said alkyl radical possibly forming with the nitrogen                atom to which it is attached a saturated or unsaturated,                optionally substituted 5- to 7-membered heterocycle,                optionally comprising at least one other nitrogen or                non-nitrogen heteroatom;    -   a cyclic or heterocyclic radical, or a non-aromatic part of an        aryl or heteroaryl radical, which may also be substituted with        one or more oxo groups;    -   an “aryl” radical represents a monocyclic or fused or non-fused        polycyclic carbon-based group comprising from 6 to 22 carbon        atoms, at least one ring of which is aromatic; preferentially,        the aryl radical is a phenyl, biphenyl, naphthyl, indenyl,        anthracenyl or tetrahydronaphthyl;    -   a “cationic heteroaryl radical” is a heteroaryl group as defined        previously, which comprises an endocyclic or exocyclic cationic        group,        -   when the charge is endocyclic, it is included in the            electron delocalization via the mesomeric effect; for            example, it is a pyridinium, imidazolium or indolinium            group:

-   -   -   with R and R′ being a heteroaryl substituent as defined            previously and particularly a (hydroxy)C₁-C₈)alkyl group,            such as methyl;        -   when the charge is exocyclic, it is not included in the            electron delocalization via the mesomeric effect; for            example, it is an ammonium or phosphonium substituent R+,            such as trimethylammonium, which is outside the heteroaryl,            such as pyridyl, indolyl, imidazolyl or naphthalimidyl, in            question:

-   -   -   with R being a heteroaryl substituent as defined below and            R⁺ an ammonium R_(a)R_(b)R_(c)N⁺—, phosphonium            R_(a)R_(b)R_(c)P⁺— or ammonium            R_(a)R_(b)R_(c)N⁺—(C₁-C₆)alkylamino,            R_(a)R_(b)R_(c)N⁺—(C₁-C₆)alkyl or            R_(a)R_(b)R_(c)N⁺—(C₁-C₆)alkoxy group with R_(a), R_(b) and            R_(c), which may be identical or different, representing a            (C₁-C₈)alkyl group such as methyl;

    -   a “heteroaryl radical” represents a 5- to 22-membered,        monocyclic or fused or non-fused polycyclic group, comprising        from 1 to 6 heteroatoms chosen from nitrogen, oxygen and sulfur,        at least one ring of which is aromatic; preferentially, a        heteroaryl radical is chosen from acridinyl, benzimidazolyl,        benzobistriazolyl, benzopyrazolyl, benzopyridazinyl,        benzoquinolyl, benzothiazolyl, benzotriazolyl, benzoxazolyl,        pyridinyl, tetrazolyl, dihydrothiazolyl, imidazopyridinyl,        imidazolyl, indolyl, isoquinolyl, naphthoimidazolyl,        naphthoxazolyl, naphthopyrazolyl, oxadiazolyl, oxazolyl,        oxazolopyridyl, phenazinyl, phenoxazolyl, pyrazinyl, pyrazolyl,        pyrilyl, pyrazoyltriazyl, pyridyl, pyridinoimidazolyl, pyrrolyl,        quinolyl, tetrazolyl, thiadiazolyl, thiazolyl,        thiazolopyridinyl, thiazoylimidazolyl, thiopyrylyl, triazolyl,        xanthylyl and the ammonium salt thereof;

    -   a “heterocyclic radical” is a radical which may contain one or        two unsaturations, but is a monocyclic or fused or non-fused        polycyclic, 5- to 22-membered non-aromatic radical comprising        from 1 to 6 heteroatoms chosen from nitrogen, oxygen and sulfur;

    -   a “heterocycloalkyl radical” is a heterocyclic radical        comprising at least one saturated ring;

    -   an “alkyl radical” is a linear or branched C₁ to C₂₀, preferably        C₁ to C₁₀, more preferentially C₁ to C₈, better still C₁ to C₆        and even better still C₁ to C₄ hydrocarbon-based radical;

    -   the expression “optionally substituted” applied to the alkyl        radical implies that said alkyl radical may be substituted with        one or more radicals chosen from the following radicals: i)        hydroxyl, ii) C₁-C₄ alkoxy, iii) R—Z—C(X)—Y— with X, Y and Z        representing an oxygen or sulfur atom or N(R′), or alternatively        X and/or Z represent a bond, R and R′, which may be identical or        different, represent a hydrogen atom or a (C₁-C₆)alkyl group,        preferably, X represents an oxygen atom, iv) amino optionally        substituted with one or two identical or different C₁-C₄ alkyl        radicals, said alkyl radicals possibly forming, with the        nitrogen atom that bears them, a 5- to 7-membered heterocycle,        optionally comprising another nitrogen or non-nitrogen        heteroatom; v) or a quaternary ammonium group N⁺R′R″R′″, M⁻ for        which R′, R″ and R′″, which may be identical or different,        represent a C₁-C₄ alkyl group, or alternatively —N⁺R′R″R′″ forms        a heteroaryl such as imidazolium optionally substituted with a        C₁-C₄ alkyl group and M⁻ represents the anionic counterion, vi)        carboxyl C(O)OH, vii) carboxylate C(O)O⁻, M⁺ with M⁺        representing a cationic counterion such as alkali metal or        alkaline-earth metal, viii) sulfonic —SO₃H, ix) sulfonate —SO₃        ⁻, M⁺ with M⁺ as defined previously, and x) cyano;

    -   an “alkoxy radical” is an alkyl-oxy radical for which the alkyl        radical is a linear or branched C₁-C₈ and preferentially C₁-C₆        hydrocarbon-based radical;

    -   when the alkoxy group is optionally substituted, this implies        that the alkyl group is optionally substituted as defined above;

    -   the term “organic or mineral acid salt” more particularly means        the salts chosen from a salt derived from i) hydrochloric acid        HCl, ii) hydrobromic acid HBr, iii) sulfuric acid H₂SO₄, iv)        alkylsulfonic acids: Alk-S(O)₂OH such as methanesulfonic acid        and ethanesulfonic acid; v) arylsulfonic acids: Ar—S(O)₂OH such        as benzenesulfonic acid and toluenesulfonic acid; vi) citric        acid; vii) succinic acid; viii) tartaric acid; ix) lactic        acid; x) alkoxysulfinic acids: Alk-O—S(O)—OH such as        methoxysulfinic acid and ethoxysulfinic acid; xi)        aryloxysulfinic acids such as tolueneoxysulfinic acid and        phenoxysulfinic acid; xii) phosphoric acid H₃PO₄; xiii) acetic        acid CH₃C(O)—OH; xiv) triflic acid CF₃SO₃H; and xv)        tetrafluoroboric acid HBF₄;

    -   the term “anionic counterion” means an anion or an anionic group        derived from an organic or mineral acid which counterbalances        the cationic charge of the dye; more particularly, the anionic        counterion is chosen from: i) halides such as chloride or        bromide; ii) nitrates; iii) sulfonates, including C₁-C₆        alkylsulfonates: Alk-S(O)₂O⁻ such as methylsulfonate or mesylate        and ethylsulfonate; iv) arylsulfonates: Ar—S(O)₂O⁻ such as        benzenesulfonate and toluenesulfonate or tosylate; v)        carboxylates Alk-C(O)—OH with Alk representing a (C₁-C₆)alkyl        group optionally substituted with one or more hydroxyl or        carboxylate groups such as citrate; vi) succinate; vii)        tartrate; viii) lactate; ix) alkyl sulfates: Alk-O—S(O)O⁻ such        as methyl sulfate and ethyl sulfate; x) aryl sulfates:        Ar—O—S(O)O⁻ such as benzene sulfate and toluene sulfate; xi)        alkoxy sulfates: Alk-O—S(O)₂O⁻ such as methoxy sulfate and        ethoxy sulfate; xii) aryloxy sulfates: Ar—O—S(O)₂O⁻, xiii)        phosphates O═P(OH)₂—O⁻. O═P(O⁻)₂—OH O═P(O⁻)₃,        HO—[P(O)(O⁻)]_(w)—P(O)(O⁻)₂ with w being an integer; xiv)        acetate; xv) triflate; and xvi) borates such as        tetrafluoroborate, and xvii) sulfate (O═)₂S(O⁻)₂ or SO₄ ²⁻ and        hydrogen sulfate HSO₄ ⁻;

    -   the anionic counterion, derived from the organic or mineral acid        salt, ensures the electrical neutrality of the molecule; thus,        it is understood that when the anion comprises several anionic        charges, then the same anion may serve for the electrical        neutrality of several cationic groups in the same molecule or        else may serve for the electrical neutrality of several        molecules; for example, a dye which contains two cationic groups        may contain either two “singly charged” anionic counterions or a        “doubly charged” anionic counterion such as (O═)₂S(O⁻)₂ or        O═P(O⁻)₂—OH;

    -   in particular, the anionic counterions are chosen from halides        such as chloride, bromide, fluoride or iodide; a hydroxide; a        sulfate; a hydrogen sulfate; a linear or branched C₁-C₆ alkyl        sulfate, such as the methylsulfate or ethylsulfate ion;        carbonates and hydrogen carbonates; carboxylic acid salts such        as formate, acetate, citrate, tartrate and oxalate; linear or        branched C₁-C₆ alkylsulfonates, such as the methylsulfonate ion;        arylsulfonates for which the aryl part, preferably phenyl, is        optionally substituted with one or more C₁-C₄ alkyl radicals,        for instance 4-tolylsulfonate; and alkylsulfonyls such as        mesylate;

    -   the term “chemical oxidizing agent” means any oxidizing agent        other than atmospheric oxygen conventionally used in the field.        Thus, mention may be made of hydrogen peroxide, urea peroxide,        alkali metal bromates, persalts such as perborates and        persulfates, and also enzymes, among which mention may be made        of peroxidases, 2-electron oxidoreductases such as uricases, and        4-electron oxygenases such as laccases. Preferably, the chemical        oxidizing agent is hydrogen peroxide.

    -   Moreover, the addition salts that may be used in the context of        the invention are especially chosen from salts of addition with        a cosmetically acceptable base such as the basifying agents as        defined below, for instance alkali metal hydroxides, such as        sodium hydroxide or potassium hydroxide, aqueous ammonia, amines        or alkanolamines;

    -   the expression “at least one” is equivalent to “one or more”;

    -   the limits of a range of values are included in that range, in        particular in the expressions “between” and “ranging from . . .        to . . . ”; and

    -   the expression “inclusive” for a range of values means that the        limits of that range are included in the defined range.

(a) Triarylmethane Dyes

The process for dyeing keratin fibres and the cosmetic compositionaccording to the present invention use, or comprise, (a) one or moretriarylmethane dyes chosen from the compounds of formula (I), as definedpreviously, the optical isomers thereof, the geometrical isomersthereof, the tautomers thereof, the organic or mineral acid or basesalts thereof, the solvates thereof such as hydrates, and mixturesthereof.

In particular, the dyes of formula (I) are blue, violet or green, anddull or chromatic.

Preferably, R₁, R₂, R′₁ and R′₂, which may be identical or different,represent, independently of each other:

-   -   a hydrogen atom,    -   a linear or branched C₁ to C₆ alkyl radical, which is optionally        substituted, and/or optionally interrupted with one or more        heteroatoms chosen from oxygen and sulfur, and/or with one or        more groups comprising at least one heteroatom, preferably        chosen from oxygen, sulfur, C(O), SO, SO₂ and SO₃ ⁻, or        combinations thereof, preferably an unsubstituted linear or        branched C₁ to C₆ alkyl radical, and more preferentially an        unsubstituted linear or branched C₁ to C₄ alkyl radical, or    -   a benzyl radical substituted with an SO₃ ⁻ group.

Preferably, n and m, which may be identical or different, represent twointegers ranging from 0 to 2. According to a particular embodiment, nand m are identical and are equal to 0.

Preferably, R₅ represents:

-   -   a hydrogen atom,    -   an SO₃ ⁻ group, or    -   a radical —NR₆R₇, with R₆ and R₇, which may be identical or        different, representing, independently of each other, a hydrogen        atom or a linear or branched C₁ to C₆ alkyl radical, and        preferably a C₁ to C₄ alkyl radical, such as a methyl or ethyl        radical.

The triarylmethane dye(s) chosen from the compounds of formula (I) ofthe invention, as defined previously, the optical isomers thereof, thegeometrical isomers thereof, the tautomers thereof, the organic ormineral acid or base salts thereof, the solvates thereof such ashydrates, and mixtures thereof, may be cationic, anionic or nonionic.

According to a particular embodiment of the invention, thetriarylmethane dye(s) are cationic (i.e. they comprise an ammonium groupon the phenyl group A) and are chosen from the compounds of formula(I-cat), they may comprise an anion An⁻ as defined previously tocounterbalance the cationic charge.

Another variant is that the dye(s) of formula (I-cat) comprise a radicalcomprising a sulfate radical SO³⁻ on one of the rings A, B or C, inwhich case the dyes of formula (I) may not comprise an anion An⁻ orcation M⁺, the sulfonate group electro-compensating for the cationiccharge of the ammonium (zwitterionic dye).

in which formula (I-cat):R₁ to R₅, and R′₁ to R′₃, m, n and q are as defined previously; it beingunderstood that (I-cat) does not comprise more than one sulfonate group.

According to another particular embodiment of the invention, thetriarylmethane dye(s) are anionic (i.e. either they comprise an ammoniumgroup attached to phenyl A and at least two sulfonate groups SO³⁻ onring A, B or C; or they do not comprise an ammonium group on A andcomprise at least one sulfonate group SO³⁻ on one of the rings A, B orC) and are chosen from the compounds of formula (I-an′) or (I-an″), thedyes then comprise one or more cations M⁺ as defined previously tocounterbalance the anionic charge(s):

in which formula (I-an′) or (I-an″):R₁ to R₅, and R′₁ to R′₃, m, n and q are as defined previously; it beingunderstood that:

-   -   (I-an′) comprises at least two sulfonate groups on ring A, B or        C,    -   (I-an″) comprises at least one sulfonate group on ring A, B or        C, and    -   one or more cation(s) M⁺ as defined previously are present to        compensate for the anionic charge(s) of the sulfonate group(s).

According to yet another particular embodiment of the invention, thetriarylmethane dye(s) are nonionic (i.e. they do not comprise anammonium group attached to phenyl A or a sulfonate group SO³⁻) and arechosen from the compounds of formula (I-nion):

in which formula (I-nion):R₁ to R₅, and R′₁ to R′₃, m, n and q are as defined previously, it beingunderstood that (I-nion) does not comprise any sulfonate groups on ringA, B or C.

According to a particular embodiment of the invention, An⁻ denotes ananion, chosen from halide ions such as bromide or chloride,methylsulfate, toluenesulfonate or a mixture of these ions, and morepreferentially An⁻ denotes a chloride.

According to a particular embodiment of the invention, M⁺ is chosen fromsodium, potassium, magnesium and calcium, preferably potassium.

According to a third particular embodiment of the invention, the dye(s)of formula (I) comprise one or more solvates and are preferentiallychosen from hydrochloride and phosphonate.

Preferably, the triarylmethane dye(s) are chosen from the followingcompounds, the optical isomers thereof, the geometrical isomers thereof,the tautomers thereof, the organic or mineral acid or base saltsthereof, the solvates thereof such as hydrates, and mixtures thereof:

Y being as defined previously.

More preferentially, the triarylmethane dye(s) are chosen from compounds1a to 14a below, the optical isomers thereof, the geometrical isomersthereof, the tautomers thereof, the organic or mineral acid or basesalts thereof, the solvates thereof such as hydrates, and mixturesthereof:

Commercial name Compound Acid Magenta Calcium Salt

Solvent Violet 8

CI Basic Blue 11

Wool Green S CI 44090

Disulfine Blue

Primocyanine 6GX

Brilliant Acid Green

Coomassie Violet

Lissamine Green V

Alkali Fast Green 10GA 1293

Coomassie Brilliant Blue FF

Carbolfuchsin

Brilliant Blue G

HCBlue 15

Basic Violet 2

According to a first particular embodiment:

-   -   R₁, R₂, R′₁ and R′₂, which may be identical or different,        represent, independently of each other:        -   a hydrogen atom,        -   an unsubstituted, linear or branched C₁ to C₆ alkyl radical,            and more preferentially an unsubstituted, linear or branched            C₁ to C₄ alkyl radical, such as a methyl or ethyl radical,        -   a benzyl radical substituted with an SO₃ ⁻ group;    -   n and m are identical and equal to 0;    -   the radicals R₄, which may be identical or different, represent,        independently of each other:        -   a linear or branched C₁ to C₆ alkyl radical, preferably a            linear or branched C₁ to C₄ alkyl radical, such as a methyl            radical,        -   a hydroxyl radical,        -   an SO₃ ⁻ group,        -   a halogen atom, preferably a chlorine atom,        -   or alternatively two adjacent radicals R₄ together form a            benzo ring, optionally substituted with an SO₃ ⁻ group;    -   q is an integer ranging from 0 to 4; and    -   R₅ represents:        -   a hydrogen atom,        -   an SO₃ ⁻ group,        -   a radical —NR₆R₇, with R₆ and R₇, which may be identical or            different, representing, independently of each other, a            linear or branched C₁ to C₆ alkyl radical, and preferably a            C₁ to C₄ alkyl radical, such as a methyl or ethyl radical.

According to a second particular embodiment:

-   -   R₁, R₂, R′₁ and R′₂, which may be identical or different,        represent, independently of each other:        -   a hydrogen atom,        -   an unsubstituted, linear or branched C₁ to C₆ alkyl radical,            and more preferentially an unsubstituted, linear or branched            C₁ to C₄ alkyl radical, such as a methyl or ethyl radical,        -   a benzyl radical substituted with an SO₃ ⁻ group;    -   n and m, which may be identical or different, are equal to 1 or        2;    -   R₃ and R′₃, which may be identical or different, represent,        independently of each other:        -   a linear or branched C₁ to C₄ alkyl radical, preferably a            methyl radical,        -   an SO₃ ⁻ group,    -   the radicals R₄, which may be identical or different, represent,        independently of each other:        -   a linear or branched C₁ to C₆, preferably linear or branched            C₁ to C₄, alkyl radical, such as a methyl radical,        -   an SO₃ ⁻ group,        -   a halogen atom, preferably a chlorine atom,    -   q is an integer equal to 1 or 2; and    -   R₅ represents:        -   a hydrogen atom,        -   an SO₃ ⁻ group,        -   a radical —NR₆R₇, with R₆ and R₇, which may be identical or            different, representing, independently of each other, a            hydrogen atom or a linear or branched C₁ to C₆ alkyl            radical, and preferably a C₁ to C₄ alkyl radical, such as a            methyl or ethyl radical.

Preferably, the triarylmethane dye(s) are chosen from compounds 1 to 15,as defined previously, the optical isomers thereof, the geometricalisomers thereof, the tautomers thereof, the organic or mineral acid orbase salts thereof, the solvates thereof such as hydrates, and mixturesthereof; and more preferentially from compounds 1a to 14a, as definedpreviously, the optical isomers thereof, the geometrical isomersthereof, the tautomers thereof, the organic or mineral acid or basesalts thereof, the solvates thereof such as hydrates, and mixturesthereof.

(b) Fluorescent Dyes

The process for dyeing keratin fibres and the composition according tothe present invention also use, or comprise, (b) one or more fluorescentdyes; said fluorescent dyes being direct dyes chosen from cyanin dyes,styryl/hemicyanin dyes, naphthalimide dyes, and mixtures thereof.

More particularly, the fluorescent dye(s) of the invention are otherthan fluorescent dyes comprising a disulfide bond. More preferentially,the fluorescent dye(s) of the invention are direct dyes and do notcomprise a bond containing contiguous identical heteroatoms.

Mention may also be made of the fluorescent dyes described in EP 1 133975, WO 03/029 359, EP 860 636, WO 95/01772, WO 95/15144, EP 714 954 andthose listed in the encyclopaedia The chemistry of synthetic dyes by K.Venkataraman, 1952, Academic Press, vol. 1 to 7, in Kirk Othmer'sencyclopaedia Chemical Technology, in the chapter “Dyes and DyeIntermediates”, 1993, Wiley and Sons, and in various chapters ofUllmann's Encyclopedia of Industrial Chemistry 7th edition, Wiley andSons, especially in Ullmann's Encyclopedia of Industrial Chemistry inthe chapter “Fluorescent Dyes”, 2005, Wiley-VCH Verlag GmbH & Co. KGaA,Weinheim 10.1002/143560007.a11_279; in The Handbook —A Guide toFluorescent Probes and Labeling Technologies, 10th Ed MolecularProbes/Invitrogen—Oregon 2005 circulated by Internet or in the precedingprinted editions.

Preferably, the fluorescent dye(s) of the invention are cationic.

More preferentially, the fluorescent dyes are direct and cationic; andbetter still, the fluorescent dye(s) (b) are chosen from styryl orhemicyanin cationic dyes.

Better still, the fluorescent dyes of the invention absorb light in theyellow, orange and red range, preferably in the absorption wavelengthλ_(abs) between 400 nm and 500 nm inclusive.

According to one variant, the fluorescent dyes of the invention containat least one cationic radical borne by, or included in, at least one ofthe fluorescent chromophores.

Preferably, the cationic radical is a quaternary ammonium; better still,the cationic charge is endocyclic.

These cationic radicals are, for example, a cationic radical:

-   -   bearing an exocyclic (di/tri)C₁-C₈)alkylammonium charge, or    -   bearing an endocyclic charge, such as the following cationic        heteroaryl groups: acridinium, benzimidazolium,        benzobistriazolium, benzopyrazolium, benzopyridazinium,        benzoquinolium, benzothiazolium, benzotriazolium, benzoxazolium,        bipyridinium, bis-tetrazolium, dihydrothiazolium,        imidazopyridinium, imidazolium, indolium, isoquinolium,        naphthoimidazolium, naphthoxazolium, naphthopyrazolium,        oxadiazolium, oxazolium, oxazolopyridinium, oxonium,        phenazinium, phenoxazolium, pyrazinium, pyrazolium,        pyrazoyltriazolium, pyridinium, pyridinoimidazolium, pyrrolium,        pyrylium, quinolium, tetrazolium, thiadiazolium, thiazolium,        thiazolopyridinium, thiazoylimidazolium, thiopyrylium,        triazolium or xanthylium.

According to a preferred variant of the invention, the fluorescent dyesof the invention bear at least one cationic chromophore and comprise atleast one quaternary ammonium radical such as polymethine chromophoreschosen from formulae (III) and (IV) below:

W⁺—[C(R^(c))═C(R^(d))]_(m′)—Ar′-(*)Q⁻  (III)

Ar—[C(R^(d))═C(R^(c))]_(m′)—W′⁺-(*)Q⁻  (IV),

in which formulae (III) and (IV):

-   -   W⁺ represents a cationic heteroaryl group, in particular        comprising a quaternary ammonium optionally substituted with one        or more (C₁-C₈)alkyl groups optionally substituted in particular        with one or more hydroxyl groups;    -   W′⁺ represents a divalent heteroaryl radical as defined for W⁺;    -   Ar represents an aryl group such as phenyl or naphthyl,        optionally substituted preferably with i) one or more halogen        atoms such as chlorine or fluorine; ii) one or more (C₁-C₈)alkyl        and preferably C₁-C₄ alkyl groups such as methyl; iii) one or        more hydroxyl groups; iv) one or more (C₁-C₈)alkoxy groups such        as methoxy; v) one or more hydroxy(C₁-C₈)alkyl groups such as        hydroxyethyl, vi) one or more amino or (di)(C₁-C₈)alkylamino        groups, preferably with the C₁-C₄ alkyl part optionally        substituted with one or more hydroxyl groups, such as        (di)hydroxyethylamino, vii) with one or more acylamino        groups; viii) one or more heterocycloalkyl groups such as        piperazinyl, piperidyl or 5- or 6-membered heteroaryl such as        pyrrolidinyl, pyridyl and imidazolinyl;    -   Ar′ is a divalent aryl radical as defined for Ar;    -   m′ represents an integer between 1 and 4 inclusive, in        particular, m′ is 1 or 2; better still 1;    -   R^(c) and R^(d), which may be identical or different, represent        a hydrogen atom or optionally a substituted (C₁-C₈)alkyl and        preferably C₁-C₄ alkyl group, or alternatively R^(c) is        contiguous with W or W′ and/or R^(d) is contiguous with Ar or        Ar′ and form, with the atoms that bear them, a        (hetero)cycloalkyl; in particular, R^(c) is contiguous with W⁺        or W′⁺ and forms a (hetero)cycloalkyl such as cyclohexyl;    -   Q⁻ is an organic or mineral anionic counterion;    -   (*) represents the part of the fluorescent chromophore that is        bonded to the rest of the dye.

Preferably, W⁺ or W′⁺ is an imidazolium, pyridinium, benzimidazolium,pyrazolium, benzothiazolium or quinolinium radical optionallysubstituted with one or more identical or different C₁-C₄ alkylradicals.

According to a particularly preferred embodiment of the invention, thefluorescent chromophore(s) of the dyes (III) or (IV) are those definedpreviously with m′=1, Ar representing a phenyl group substituted para tothe styryl group —C(R^(d))═C(R^(c))— with a(di)(hydroxy)(C₁-C₆)(alkyl)amino group such asdihydroxy(C₁-C₄)alkylamino, and W′⁺ representing an imidazolium orpyridinium group, preferentially ortho- or para-pyridinium.

According to another preferred variant of the invention, the fluorescentchromophore(s) of the dyes are cationic and comprise at least onequaternary ammonium radical such as a naphthimidyl bearing a cationicexocyclic charge of formula (IIIa) or (IVa):

-   -   where        represents the bond with the dye        in which formulae (IIIa) and (IVa) R^(e), R^(f), R^(g) and        R^(h), which may be identical or different, represent a hydrogen        atom or a (C₁-C₆)alkyl group which is optionally substituted,        preferentially with a di(C₁-C₆)alkylamino or        tri(C₁-C₆)alkylammonium group such as trimethylammonium.

According to a particular embodiment, the fluorescent dye(s) (b) of theinvention are chosen from those of formula (V), (VI) or (VII) below, andalso the organic or mineral acid or base salts thereof, the opticalisomers, geometrical isomers and tautomers thereof, and the solvatesthereof such as hydrates:

in which formulae (V), (VI) and (VII):

-   -   R₁ and R₂, which may be identical or different, represent a        hydrogen atom or a C₁-C₆ alkyl group; preferentially a hydrogen        atom;    -   G₁ represents a hydrogen atom or a group chosen from NH₂ and OH;    -   R_(a), R′_(a), R″_(a), R′″_(a), R_(b), R′_(b), R″_(b) and        R′″_(b), which may be identical or different, represent a) a        hydrogen atom, b) a halogen atom, a group from among: c)        amino, d) (C₁-C₄)alkylamino, e) (C₁-C₄)dialkylamino, f)        cyano, g) carboxyl —C(O)OH or carboxylate —C(O)O⁻, Q⁺, h)        hydroxyl —OH or alkoxide —O⁻Q⁺, i) (poly)halo(C₁-C₆)alkyl such        as trifluoromethyl, j) acylamino, k) (C₁-C₆)alkoxy, l)        (C₁-C₆)alkylthio, m) (poly)hydroxy(C₂-C₄)alkoxy, n)        (C₁-C₆)alkylcarbonyloxy, o) (C₁-C₆)alkoxycarbonyl, p)        (C₁-C₆)alkylcarbonylamino, q) acylamino, r) carbamoyl, s)        (C₁-C₆)alkylsulfonylamino, t) aminosulfonyl, u) —SO₃H or        sulfonate —SO₃ ⁻, Q⁺ or v) (C₁-C₆)alkyl optionally substituted        with a group chosen from (C₁-C₆)alkoxy, hydroxyl, cyano,        carboxyl, amino, (di)(C₁-C₄)alkylamino, or alternatively the two        alkyl radicals borne by the nitrogen atom of the amino group        form a 5- to 7-membered heterocycle optionally comprising        another nitrogen or non-nitrogen heteroatom; in particular,        R_(a), R′_(a), R″_(a), R′″_(a), R_(b), R′_(b), R″_(b) and        R′″_(b) represent a hydrogen or halogen atom or a (C₁-C₄)alkyl        group, preferably a hydrogen atom;    -   or alternatively two groups R_(a) and R′_(a); R_(b) and R′_(b)        borne by two adjacent carbon atoms together form a benzo or        indeno ring, a fused heterocycloalkyl or fused heteroaryl group;        the benzo, indeno, heterocycloalkyl or heteroaryl ring being        optionally substituted with a halogen atom, an amino,        (C₁-C₄)alkylamino, (C₁-C₄)dialkylamino, nitro, cyano, carboxyl,        hydroxyl or trifluoromethyl group, an acylamino, (C₁-C₄)alkoxy        (poly)hydroxy(C₁-C₄)alkoxy, (C₁-C₄)alkylcarbonyloxy,        (C₁-C₄)alkoxycarbonyl or (C₁-C₄)alkylcarbonylamino radical, an        acylamino, carbamoyl or alkoxyalkylsulfonylamino radical, an        aminosulfonyl radical, or a (C₁-C₆)alkyl radical optionally        substituted with: a group chosen from (C₁-C₆)alkoxy, hydroxyl,        cyano, carboxyl, amino, (C₁-C₄)alkylamino and        (C₁-C₄)dialkylamino, or alternatively the two alkyl radicals        borne by the nitrogen atom of the amino group form a 5- to        7-membered heterocycle optionally comprising another nitrogen or        non-nitrogen heteroatom; preferentially, R_(a) and R′_(a)        together form a benzo group;    -   or alternatively, two groups R_(i) and R_(a); and/or a group        R′_(i) and R′_(a) together form a fused (hetero)cycloalkyl,        preferentially cycloalkyl such as cyclohexyl;    -   R_(g) represents a hydrogen atom, a (hetero)aryl(C₁-C₄)alkyl        group or a (C₁-C₆)alkyl group that is optionally substituted;        preferentially, R_(b) represents a hydrogen atom or a        (C₁-C₃)alkyl or benzyl group;    -   R_(e) represents a covalent bond, a linear or branched,        optionally substituted (C₁-C₈)alkylene or (C₂-C₈)alkenylene        hydrocarbon-based chain, preferably R_(e) represents an        unsubstituted (C₁-C₆)alkylene;    -   R_(f) represents a hydrogen atom, a (C₁-C₄)alkoxy group, an        amino group R₃R₄N—, a quaternary ammonium group M′, R₃R₄R₅N⁺— in        which R₃, R₄ and R₅, which may be identical or different,        represent a (C₁-C₄)alkyl group or R₃R₄N-represents an optionally        substituted heteroaryl group, preferentially an optionally        substituted imidazolyl group, or alternatively M′, R₃R₄R₅N⁺—        represents an optionally substituted cationic heteroaryl group,        preferentially an imidazolinium group optionally substituted        with a (C₁-C₃)alkyl group;    -   G represents i) a group —NR_(c)R_(d), ii) —OR with R        representing a) a hydrogen atom, b) an optionally substituted,        preferentially unsubstituted (C₁-C₆)alkyl group, c) an        optionally substituted (hetero)aryl group, d) an optionally        substituted (hetero)aryl(C₁-C₆)alkyl group such as benzyl, e)        optionally substituted (hetero)cycloalkyl, f) optionally        substituted (hetero)cycloalkyl(C₁-C₆)alkyl; according to a        particular embodiment, G represents a group —NR_(c)R_(d),        according to another particular embodiment, G represents a        (C₁-C₆)alkoxy group;    -   or alternatively when G represents —NR_(c)R_(d), two groups        R_(c) and R′_(a) and/or R_(d) and R_(a) together form a        saturated heteroaryl or heterocycle, optionally substituted with        one or more (C₁-C₆)alkyl groups, preferentially a 5- to        7-membered heterocycle containing one or two heteroatoms chosen        from nitrogen and oxygen; more preferentially, the heterocycle        is chosen from morpholinyl, piperazinyl, piperidyl and        pyrrolidinyl groups;    -   R_(c) and R_(d), which may be identical or different, represent        a hydrogen atom or a group from among: a) optionally substituted        (hetero)aryl such as phenyl, b) optionally substituted        (hetero)aryl(C₁-C₄)alkyl, c) optionally substituted        (hetero)cycloalkyl, d) optionally substituted        (hetero)cycloalkyl(C₁-C₄)alkyl, f) (C₂-C₅)alkyl or g)        (C₁-C₈)alkyl which is optionally substituted, preferably        optionally substituted with a hydroxyl, carboxyl, carboxylate,        sulfate or sulfonate group;    -   or alternatively two adjacent radicals R_(c) and R_(d) borne by        the same nitrogen atom together form an optionally substituted        heterocyclic or optionally substituted heteroaryl group;    -   R_(i) and R′_(i), which may be identical or different, represent        a hydrogen atom or a (C₁-C₄)alkyl group;

represents a (hetero)aryl group fused to the phenyl ring; oralternatively is absent from the phenyl; preferentially, when the ringis present, the ring is a benzo;

-   -   m represents an integer between 1 and 18 inclusive, particularly        an integer between 1 and 14 inclusive; preferentially an integer        between 2 and 10 inclusive; more preferentially an integer        between 3 and 8; more particularly an integer between 4 and 6;    -   M′ represents an anionic counterion, derived from a salt of an        organic or mineral acid, or from an organic or mineral base that        ensures the electrical neutrality of the dye;    -   Q⁺ represents a cationic counterion, derived from a salt of an        organic or mineral acid, or from an organic or mineral base that        ensures the electrical neutrality of the dye such as alkali        metal, alkaline-earth metal or ammonium;        it being understood that when the dye comprises a carboxylate,        sulfonate or alkoxide group, then M′ and Q⁺ may be absent to        ensure the electrical neutrality of said dye.

According to one embodiment, the fluorescent dyes of the invention areof formula (V) as defined previously.

According to a preferred embodiment, the fluorescent dye(s) of theinvention are chosen from the styryl dyes of formula (VIII) below, andalso the organic or mineral acid or base salts thereof, the opticalisomers, geometrical isomers and tautomers thereof, and the solvatesthereof such as hydrates:

in which formula (VIII) G, G₁, R_(a), R′_(a), R″_(a), R_(b), R′_(b),R″_(b), R_(i), R′_(i), R₁, R₂ and m are as defined previously for (V).

In particular, the dye(s) of the invention are chosen from those offormula (VIII) for which:

-   -   R₁ and R₂, which may be identical or different, represent a        hydrogen atom;    -   R_(i) and R′_(i), which may be identical or different, represent        a hydrogen atom or a (C₁-C₄)alkyl group, preferably hydrogen;    -   R_(a), R′_(a) and R″_(a), which may be identical or different,        represent a hydrogen atom, a halogen atom such as fluorine, or        an —OH, —O⁻Q⁺, (C₁-C₆)alkoxy, nitro, or cyano group, with Q⁺ as        defined previously;    -   R_(b), R′_(b) and R″_(b), which may be identical or different,        represent a hydrogen atom or a (C₁-C₆)alkyl group;    -   or alternatively two contiguous radicals R_(b) and R′_(b) form,        together with the carbon atoms that bear them, a benzo group        that is condensed or fused to the pyridinium group, said benzo        group possibly being substituted; preferably, said benzo group        is unsubstituted;    -   G represents a group —NR_(c)R_(d) or (C₁-C₆)alkoxy group which        is optionally substituted, preferentially unsubstituted;        according to a particular embodiment, G represents a group        —NR_(c)R_(d), according to another particular embodiment, G        represents a (C₁-C₆)alkoxy group;    -   R_(i) and R′_(i), which may be identical or different, represent        a hydrogen atom or a (C₁-C₄)alkyl group;

represents an aryl or heteroaryl group fused to the phenyl ring; oralternatively is absent from the phenyl ring; preferentially, when thering is present, the ring is a benzo;

-   -   m represents an integer between 1 and 18 inclusive; particularly        an integer between 2 and 16 inclusive; preferentially an integer        between 3 and 10; more preferentially an integer between 4 and        6;    -   R_(c) and R_(d), which may be identical or different, represent        a hydrogen atom, a (C₂-C₄)alkyl group or a substituted        (C₁-C₈)alkyl group, preferably (C₂-C₄)alkyl substituted in        particular with one or more groups chosen from i) cyano, ii)        (C₁—C₃)alkoxy, iii) hydroxyl and iv) (C₁-C₃)alkylcarbonyl,        preferably with one or more hydroxyl groups; and    -   M′ representing an anionic counterion, derived from a salt of an        organic or mineral acid, or from an organic or mineral base that        ensures the electrical neutrality of the dye;        it being understood that when the dye comprises an alkoxide        group, then M′ and Q⁺ may be absent to ensure the electrical        neutrality of said dye.

Preferably, the fluorescent dye(s) (b) of the invention are chosen fromthe styryl dyes of formula (IX) below, and also the organic or mineralacid or base salts thereof, the optical isomers, geometrical isomers andtautomers thereof, and the solvates thereof such as hydrates:

in which formula (IX) G, G₁, R_(a), R′_(a), R_(b), R′_(b) and m are asdefined previously.

According to a particular embodiment, the group G is in the paraposition relative to the —CH═CH— group, i.e. in position 4′ of thephenyl group. According to another particular embodiment of theinvention, the group G is in the ortho position relative to the —CH═CH—group, i.e. in position 2′ of the phenyl group. According to oneembodiment, the —CH═CH— group is in the para position of the pyridiniumgroup, i.e. in position 4.

According to another advantageous variant, the —CH═CH— group is in theortho position of the pyridinium group, i.e. in position 2.

According to a preferred mode of the invention, the fluorescent dye(s)(b) of the invention are chosen from the compounds of formulae (X) and(XI) below, and also the organic or mineral acid or base salts thereof,the optical isomers, geometrical isomers and tautomers thereof, and thesolvates thereof such as hydrates:

in which formulae (X) and (XI):

-   -   R¹, R², R³ and R⁴, which may be identical or different,        represent a hydrogen atom or a (C₁-C₆)alkyl group; preferably,        R² and R³ represent a hydrogen atom and R¹ and R⁴, which may be        identical or different, represent a hydrogen atom or a        (C₁-C₄)alkyl group;    -   R⁵, R⁶, R⁷, R⁸ and R⁹, which may be identical or different,        represent i) a hydrogen atom or ii) a halogen atom such as Cl,        Br or F, iii) a group OR in which R represents a hydrogen atom        or Q⁺ as described previously, or a (C₁-C₃)alkyl group, a group        from among iv) aryl such as benzene, v) aryl(C₁-C₃)alkyl such as        benzyl, vi) cyano, vii) nitro, viii) (C₁-C₃)alkylthio, ix) amino        NR¹⁰R¹¹ with R¹⁰ and R¹¹, which may be identical or different,        representing a) a hydrogen atom, b) a (C₂-C₄)alkyl group or c) a        substituted (C₁-C₈)alkyl group, preferably (C₂-C₄)alkyl        optionally substituted with one or more groups chosen from:        -   cyano,        -   (C₁-C₃)alkoxy,        -   hydroxyl, and        -   (C₁-C₃)alkylcarbonyl;        -   in particular, R¹⁰ and R¹¹, which may be identical or            different, represent a hydrogen atom or a (C₁-C₆)alkyl group            substituted with one or more hydroxyl, cyano or            (C₁-C₃)alkylcarbonyl groups such as hydroxyethyl;    -   m represents an integer between 1 and 18 inclusive; particularly        an integer between 2 and 16 inclusive; preferentially an integer        between 3 and 10; more preferentially an integer between 4 and        6;    -   M′ represents an anionic counterion as defined previously;        it being understood that when the dye comprises an alkoxide        group, then M′ and Q⁺ may be absent to ensure the electrical        neutrality of said dye.

According to a first embodiment of the invention, the fluorescent dye(s)(b) are of formula (X) with:

R¹ R² R³ R⁴ R⁵ R⁶ R⁷ R⁸ R⁹ m H H H H H H H H H 1 H H H H H t-Bu OH t-BuH 5 H H H H H t-Bu OH t-Bu H 5 H H H H H H NH₂ H H 1 H H H H H H NH₂ HOCH₃ 1 H H H H H H OH Br H 5 H H H H H OCH₃ OH OCH₃ H 5 H H H H Cl H OHH Cl 5 H H H H H H OH H H 10 H H H H H OCH₃ OH OCH₃ H 10 H H H H H t-BuOH t-Bu H 10 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 HH H H H H N(CH₂CH₃)₂ H H 1 H H H H H t-Bu OH t-Bu H 10 H H H H H HN(CH₂CH₃)CH₂CH₂OH H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H HN(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H HN(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H1 H H H H H H n-C₆H₁₃ H H 1 H H H H H H N(CH₂CH₂OH)₂ H H 2 H H H H H HN(n-Bu)₂ H H 2 H H H H H OCH₃ OH H H 10 H H H H H H OC₂H₅OH H H 1 H H HH H H OH H H 1 H H benzo H H H H H 1 H H benzo H H N(CH₂CH₂OH)₂ H H 1 HH benzo H H N(CH₂CH₂OH)₂ H H 1and also the organic or mineral acid or base salts thereof, the opticalisomers, geometrical isomers and tautomers thereof, and the solvatesthereof such as hydrates.

According to a second embodiment, the fluorescent dye(s) (b) are offormula (XI) with:

R¹ R² R³ R⁴ R⁵ R⁶ R⁷ R⁸ R⁹ m CH₃ H H H OH H OCH₃ H H 2 CH₃ H H H H HOCH₃ OCH₂-Ph H 2 CH₃ H H H H H H H OCH₃ 2 CH₃ H H H F H H H H 2 CH₃ H HH H H H OPh H 2 CH₃ H H H H H N(CH₂CH₂OAc)₂ H H 2 CH₃ H H H OCH₃ H OCH₃OCH₃ H 2 CH₃ H H H H H H CH₃ H 2 CH₃ H H H H H OH H H 2 CH₃ H H H H OCH₃OCH₃ OCH₃ H 2 CH₃ H H H H OCH₃ OH OH H 2 CH₃ H H H H H OCH₃ OCH₃ OCH₃ 2CH₃ H H H H H H OCH₃ OH 2 CH₃ H H H H H N(n-butyl)₂ H H 2 CH₃ H H H HOCH₃ OCH₃ H H 2 CH₃ H H H H H H H H 2 CH₃ H H H H H i-propyl H H 2 H H HH H H OH H H 6 H H H H H OCH₃ OCH₃ OCH₃ H 6 H H H H OH H OCH₃ H H 2 H HH H OCH₃ H H OCH₃ OCH₃ 2 H H H H H H H H Br 2 H H H H H H OH H H 2 H H HH OCH₃ OCH₃ OCH₃ H H 6 H H H H OH OCH₃ H H H 6 H H H H H OCH₃ OCH₃ H H 6H H H H H OCH₃ OCH₃ H H 2 H H H H H H C(O)—OH H H 6 H H H H H H C(O)—OHH H 2 H H H H H H i-propyl H H 2 H H H H H H N(CH₃)CH₂CH₂CN H H 2 H H HH H H OCH₃ OCH₂Ph H 2 H H H H H H H OPh H 2 H H H H H HN(CH₂CH₂C(O)CH₃)₂ H H 2 H H H H OH H OCH₃ H H 6 H H H H H OCH₃ OCH₃ OCH₃H 2 H H H H OCH₃ H OCH₃ OCH₃ H 6 H H H H H H H CH₃ H 2 H H H H H HN(CH₃)CH₂CH₂OH H H 2and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates.

Preferably, the fluorescent dye(s) (b) are chosen from those of formulae(X′) and (XI′) below:

in which formulae (X′) and (XI′) R⁵, R⁷, R⁸ and m are as definedpreviously for (X) and (XI), in particular:

-   -   R⁵ and R⁸, which may be identical or different, represent a        hydrogen atom or a (C₁-C₄)alkoxy group such as methoxy;    -   R⁷ represents a (C₁-C₄)alkoxy group or NR¹⁰R¹¹ with R¹⁰        representing a) a hydrogen atom, or b) a (C₁-C₆)alkyl group        optionally substituted with one or more groups chosen from i)        cyano, ii) (C₁-C₃)alkoxy, iii) hydroxyl and iv)        (C₁-C₃)alkylcarbonyl and R¹¹ representing a) a (C₂-C₅)alkyl        group substituted with one or more groups chosen from i)        cyano, ii) (C₁-C₃)alkoxy, iii) hydroxyl and iv)        (C₁-C₃)alkylcarbonyl;    -   in particular, NR¹⁰R¹¹ represents a (C₂-C₄)alkyl group, a        (di)hydroxy(C₂-C₄)alkylamino or        hydroxy(C₂-C₄)alkyl((C₁-C₄)alkyl)amino group;    -   m represents an integer between 1 and 18 inclusive; particularly        an integer between 2 and 16 inclusive; preferentially an integer        between 3 and 10; more preferentially an integer between 4 and        6; and    -   M′ represents an anionic counterion, derived from a salt of an        organic or mineral acid, or from an organic or mineral base that        ensures the electrical neutrality of the dye.

According to this embodiment, the fluorescent dye(s) (b) are preferablychosen from those of formula (X′) or (XI′) with:

R⁵ R⁷ R₈ m OCH₃ OCH₃ OCH₃ 2 OCH₃ OCH₃ OCH₃ 3 OCH₃ OCH₃ OCH₃ 3 OCH₃ OCH₃OCH₃ 4 OCH₃ OCH₃ OCH₃ 5 OCH₃ OCH₃ OCH₃ 8 OCH₃ OCH₃ OCH₃ 10 OCH₃ OCH₃OCH₃ 12 OCH₃ OCH₃ OCH₃ 14 OCH₃ OCH₃ OCH₃ 16

R⁵ R⁷ R⁸ m H N(CH₂CH₂OH)₂ H 2 H N(CH₂CH₂OH)₂ H 3 H N(CH₂CH₂OH)₂ H 4 HN(CH₂CH₂OH)₂ H 5 H N(CH₂CH₂OH)₂ H 6 H N(CH₂CH₂OH)₂ H 8 H N(CH₂CH₂OH)₂ H10 H N(CH₂CH₂OH)₂ H 12 H N(CH₂CH₂OH)₂ H 14 H N(CH₂CH₂OH)₂ H 16 HCH₃CH₂N(CH₂CH₂OH) H 2 H CH₃CH₂N(CH₂CH₂OH) H 4andand also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates.

According to yet another preferred mode of the invention, thefluorescent dye(s) (b) of the invention are chosen from the compounds offormulae (XII) and (XIII) below, and also the organic or mineral acid orbase salts thereof, the optical isomers, geometrical isomers andtautomers thereof, and the solvates thereof such as hydrates:

in which formulae (XII) and (XIII):

-   -   R¹, R², R³ and R⁴, which may be identical or different,        represent a hydrogen atom or a (C₁-C₆)alkyl group; preferably,        R² and R³ represent a hydrogen atom and R¹ and R⁴, which may be        identical or different, represent a hydrogen atom or a        (C₁-C₄)alkyl group;    -   R⁵, R⁶, R⁷, R⁸ and R⁹, which may be identical or different,        represent i) a hydrogen atom or ii) a halogen atom such as Cl,        Br or F, iii) a group OR in which R represents a hydrogen atom        or Q⁺ as described previously, or a (C₁-C₃)alkyl group, a group        from among iv) aryl such as benzene, v) aryl(C₁-C₃)alkyl such as        benzyl, vi) cyano, vii) nitro, viii) (C₁-C₃)alkylthio, ix) amino        NR¹⁰R¹¹ with R¹⁰ and R¹¹, which may be identical or different,        representing a) a hydrogen atom or b) a (C₁-C₈)alkyl group        optionally substituted with one or more groups chosen from:        -   cyano,        -   (C₁-C₃)alkoxy,        -   hydroxyl, and        -   (C₁-C₃)alkylcarbonyl;        -   in particular, R¹⁰ and R¹¹, which may be identical or            different, represent a hydrogen atom or a (C₁-C₆)alkyl group            optionally substituted with one or more hydroxyl, cyano or            (C₁-C₃)alkylcarbonyl groups such as methyl, ethyl, butyl,            isobutyl, cyanoethyl, methylcarbonylethyl, or hydroxyethyl;    -   m represents an integer between 1 and 18 inclusive; particularly        an integer between 2 and 16 inclusive; preferentially an integer        between 3 and 10; more preferentially an integer between 4 and        6;    -   M′ represents an anionic counterion derived from salts of        organic or mineral acids preferably originating from Y;        it being understood that when the dye comprises an alkoxide        group, then M′ and Q⁺ may be absent to ensure the electrical        neutrality of said dye.

According to one embodiment of the invention, the fluorescent dye(s) (b)are of formula (XII) with:

R¹ R² R³ R⁴ R⁵ R⁶ R⁷ R⁸ R⁹ m H H H H H H OCH₃ OCH₃ OCH₃ 2 H H H H OHOCH₃ H H H 2 H H H H H H H H H 2 H H H H H OCH₃ OCH₃ H H 2 H H H H OH HOH H H 6 H H H H OCH₃ H OCH₃ OCH₃ H 6 H H H H H H OH H H 6 H H H H OCH₃H H H F 2 H H H H H H C(O)—OH H H 2 H H H H H H Isopropyl H H 2 H H H HH H N(CH₂CH₂C(O)CH₃)₂ H H 2 H H H H OH H OCH₃ H H 2 H H H H H H OH H H 2H H H H H OCH₃ OH OH H 2 H H H H H CH₃ OCH₂Ph CH₃ H 2 H H H H H OCH₃OCH₃ OCH₃ H 2 H H H H H OCH₃ OCH₃ OCH₃ H 6 H H H H H H N(CH₃)₂ H H 6 H HH H H H OCH₃ OCH₃ OCH₃ 6 H H H H H H Phenyl H H 6 H H H H H OCH₃ OCH₃ HH 6 H H H H H H C(O)—OH H H 6 H H H H H H N(n-Butyl)₂ H H 2 H H H H H HOCH₃ OCH₃ H 3 H H H H H H OCH₃ OCH₃ H 2 H H H H H H OCH₃ OCH₃ H 5 H H HH H H OCH₃ H H 3 H H H H H H N(CH₃)₂ H H 3 H H H H H H H H H 3and also the organic or mineral acid or base salts thereof, the opticalisomers, geometrical isomers and tautomers thereof, and the solvatesthereof such as hydrates.

According to another embodiment, the fluorescent dye(s) (b) are offormula (XIII) with:

R¹ R² R³ R⁴ R⁵ R⁶ R⁷ R⁸ R⁹ m CH₃ H H H OH H OCH₃ H H 2 CH₃ H H H H HOCH₃ OCH₂-Ph H 2 CH₃ H H H H H H H OCH₃ 2 CH₃ H H H F H H H H 2 CH₃ H HH H H H OPh H 2 CH₃ H H H H H N(CH₂CH₂OAc)₂ H H 2 CH₃ H H H OCH₃ H OCH₃OCH₃ H 2 CH₃ H H H H H H CH₃ H 2 CH₃ H H H H H OH H H 2 CH₃ H H H H OCH₃OCH₃ OCH₃ H 2 CH₃ H H H H OCH₃ OH OH H 2 CH₃ H H H H H OCH₃ OCH₃ OCH₃ 2CH₃ H H H H H H OCH₃ OH 2 CH₃ H H H H H N(n-butyl)₂ H H 2 CH₃ H H H HOCH₃ OCH₃ H H 2 CH₃ H H H H H H H H 2 CH₃ H H H H H i-propyl H H 2 H H HH H H OH H H 6 H H H H H OCH₃ OCH₃ OCH₃ H 6 H H H H OH H OCH₃ H H 2 H HH H OCH₃ H H OCH₃ OCH₃ 2 H H H H H H H H Br 2 H H H H H H OH H H 2 H H HH H H N(CH₃)₂ H H 6 H H H H OCH₃ OCH₃ OCH₃ H H 6 H H H H OH OCH₃ H H H 6H H H H H OCH₃ OCH₃ H H 6 H H H H H OCH₃ OCH₃ H H 2 H H H H H H C(O)—OHH H 6 H H H H H H C(O)—OH H H 2 H H H H H H i-propyl H H 2 H H H H H HN(CH₃)CH₂CH₂CN H H 2 H H H H H H OCH₃ OCH₂Ph H 2 H H H H H H H OPh H 2 HH H H H H N(CH₂CH₂C(O)CH₃)₂ H H 2 H H H H OH H OCH₃ H H 6 H H H H H OCH₃OCH₃ OCH₃ H 2 H H H H OCH₃ H OCH₃ OCH₃ H 6 H H H H H H H CH₃ H 2 H H H HH H N(CH₃)CH₂CH₂OH H H 2 CH₃ H H H H H N(CH₃)₂ H H 2and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates.

More particularly, the fluorescent dye(s) (b) of the invention arechosen from those of formulae (XII′) and (XIII′) below:

in which formulae (XII′) and (XIII′) R⁵, R⁷, R⁸ and m are as definedpreviously for (X) and (XI), in particular:

-   -   R⁵ and R⁸, which may be identical or different, represent a        hydrogen atom or a (C₁-C₄)alkoxy group such as methoxy;    -   R⁷ represents a (C₁-C₄)alkoxy group or NR¹⁰R¹¹ with R¹⁰ and R¹¹,        which may be identical or different, representing a) a hydrogen        atom, or b) a (C₁-C₈)alkyl group optionally substituted with one        or more groups chosen from i) cyano, ii) (C₁-C₃)alkoxy, iii)        hydroxyl, and iv) (C₁-C₃)alkylcarbonyl; in particular, R¹⁰ and        R¹¹, which may be identical or different, represent a hydrogen        atom or a (C₁-C₆)alkyl group optionally substituted with one or        more groups from the following: hydroxyl, cyano or        (C₁-C₃)alkylcarbonyl such as methyl, ethyl, butyl, isobutyl,        cyanoethyl, methylcarbonylethyl or hydroxyethyl; preferably, R¹⁰        and R¹¹, which may be identical or different, represent a        (C₁-C₆)alkyl group optionally substituted with one or more        hydroxyl groups such as hydroxyethyl;    -   m represents an integer between 1 and 18 inclusive; particularly        an integer between 2 and 16 inclusive; preferentially an integer        between 3 and 10; more preferentially an integer between 4 and        6; and    -   M′ represents an anionic counterion, derived from a salt of an        organic or mineral acid, or from an organic or mineral base that        ensures the electrical neutrality of the dye.

According to one embodiment, the fluorescent dye(s) (b) of the inventionare of formula (XII′) or (XIII′) with:

R⁵ R⁷ R₈ m H N(CH₂CH₂OH)₂ H  2 H N(CH₂CH₂OH)₂ H  3 H N(CH₂CH₂OH)₂ H  4 HN(CH₂CH₂OH)₂ H  5 H N(CH₂CH₂OH)₂ H  6 H N(CH₂CH₂OH)₂ H  8 H N(CH₂CH₂OH)₂H 10 H N(CH₂CH₂OH)₂ H 12 H N(CH₂CH₂OH)₂ H 14 H N(CH₂CH₂OH)₂ H 16and

R⁵ R⁷ R⁸ m OCH₃ OCH₃ OCH₃ 2 OCH₃ OCH₃ OCH₃ 3 OCH₃ OCH₃ OCH₃ 3 OCH₃ OCH₃OCH₃ 4 OCH₃ OCH₃ OCH₃ 5 OCH₃ OCH₃ OCH₃ 8 OCH₃ OCH₃ OCH₃ 10 OCH₃ OCH₃OCH₃ 12 OCH₃ OCH₃ OCH₃ 14 OCH₃ OCH₃ OCH₃ 16and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates.

More particularly, the fluorescent dye(s) (b) of the invention arechosen from those of formula (V), (VIII) or (IX) as defined previouslyin which G represents a hydrogen atom.

More particularly, the fluorescent dye(s) (b) of the invention arechosen from those of formulae (XIV) and (XV) below:

in which formulae (XIV) and (XV) R⁵, R⁷, R⁸ and m are as definedpreviously for (X) and (XI), in particular:

-   -   R⁵ and R⁸, which may be identical or different, represent a        hydrogen atom or a (C₁-C₄)alkoxy group such as methoxy,        preferably, R⁵ and R⁸ represent a hydrogen atom;    -   R⁷ represents a (C₁-C₄)alkoxy group or NR¹⁰R¹¹ with R¹⁰ and R¹¹,        which may be identical or different, representing a) a hydrogen        atom, or b) a (C₁-C₈)alkyl group optionally substituted with one        or more groups chosen from i) hydroxyl, ii) R—Z—C(X)—Y— with X,        Y and Z representing an oxygen or sulfur atom or N(R′), or        alternatively X and/or Z represent a bond, R and R′, which may        be identical or different, represent a hydrogen atom or a        (C₁-C₆)alkyl group, preferably, X represents an oxygen        atom, iii) sulfonic SO₃H, iv) sulfonate SO₃ ⁻, Q⁺, v)        carboxylate C(O)O⁻, Q⁺ with Q⁺ representing a cationic        counterion such as an alkali metal or alkaline-earth metal; in        particular, R⁷ represents a group NR¹⁰R¹¹ with R¹⁰ and R¹¹,        which may be identical or different, representing a) a hydrogen        atom, or b) a (C₁-C₆)alkyl group optionally substituted with one        or more groups chosen from i) hydroxyl, ii) carboxyl, iii)        carboxylate, iv) sulfonic, and v) sulfonate, more particularly        chosen from identical or different groups representing a) a        hydrogen atom, or b) a (C₁-C₆)alkyl group optionally substituted        with one or more groups chosen from i) hydroxyl, ii) carboxyl,        and iii) carboxylate;    -   m represents an integer between 1 and 18 inclusive; particularly        an integer between 1 and 6 inclusive; preferentially an integer        between 1 and 4; more preferentially an integer between 1 and 2;        and    -   M′ represents an anionic counterion, derived from a salt of an        organic or mineral acid, or from an organic or mineral base that        ensures the electrical neutrality of the dye;        it being understood that when the dye comprises a sulfonate or        carboxylate group, then M′ and Q⁺ may be absent to ensure the        electrical neutrality of said dye.

More preferentially, the fluorescent dye(s) (b) of the invention arechosen from the following compounds, and also the geometrical isomersthereof, the tautomers thereof, the solvates thereof and mixturesthereof:

with M′ and Q⁺ as defined previously.

The Oxidizing Agents

The process for dyeing keratin fibres and the cosmetic compositionaccording to the present invention may also optionally use, or comprise,one or more oxidizing agents.

Preferably, the oxidizing agent(s) are chosen from chemical oxidizingagents.

The term “chemical oxidizing agent” means an oxidizing agent other thanatmospheric oxygen.

More particularly, the chemical oxidizing agent(s) are chosen fromhydrogen peroxide, hydrogen peroxide-generating systems, urea peroxide,alkali metal bromates or ferricyanides, peroxygenated salts, forinstance persulfates, perborates, peracids and precursors thereof andpercarbonates of alkali metals or alkaline-earth metals, and mixturesthereof.

Preferably, the chemical oxidizing agent(s) are chosen from hydrogenperoxide and hydrogen peroxide-generating systems.

According to a preferred embodiment, the hydrogen peroxide-generatingsystem(s) are chosen from urea peroxide, polymeric complexes that canrelease hydrogen peroxide, chosen from polyvinylpyrrolidone/H₂O₂;oxidases; perborates; and percarbonates.

Preferably, the chemical oxidizing agent is hydrogen peroxide, and morepreferentially aqueous hydrogen peroxide solution.

The chemical oxidizing agent(s) are advantageously applied in the formof an aqueous solution of which the content of chemical oxidizing agentsis preferably between 0.05% and 5% by weight and more preferentiallybetween 0.1% and 2% by weight, relative to the total weight of theaqueous solution.

According to a preferred embodiment of the invention, the dyeing processdoes not use any oxidizing agent.

According to this preferred embodiment of the invention, the cosmeticcomposition comprising ingredients (a) and (b) does not comprise anyoxidizing agent.

The Reducing Agents

The process for dyeing keratin fibres and the cosmetic compositionaccording to the present invention may also optionally use, or comprise,one or more reducing agents.

The reducing agent(s) that are useful in the present invention areadvantageously chosen from the compounds of formula (XVI) below, andalso the addition salts thereof and mixtures thereof:

H(X)_(q)(R₁₀)_(t)  (XVI)

in which formula (XVI):

-   -   X represents P, S or SO₂,    -   q represents an integer equal to 0 or 1,    -   t represents an integer equal to 1 or 2, and    -   R represents a linear or branched, saturated or unsaturated C₁        to C₂₀ alkyl radical, optionally interrupted with a heteroatom,        and/or optionally substituted with one or more radicals chosen        from hydroxyl, halo, amine, carboxyl, ((C₁-C₃₀)alkoxy)carbonyl,        amido, ((C₁-C₃₀)alkyl)aminocarbonyl, (C₁-C₃₀)acyl)amino, mono or        dialkylamino, and mono or dihydroxylamino radicals.

Preferably, the reducing agent(s) are chosen from thioglycolic acid,thiolactic acid, glyceryl monothioglycolate, cysteamine,N-acetylcysteamine, N-propionylcysteamine, cysteine, N-acetylcysteine,thiomalic acid, pantetheine, 2,3-dimercaptosuccinic acid,N-(mercaptoalkyl)-o-hydroxyalkylamides, N-mono- orN,N-dialkylmercapto-4-butyramides, aminomercaptoalkylamides,N-(mercaptoalkyl)succinamic acid and N-(mercaptoalkyl)succinimidederivatives, alkylamino mercaptoalkylamides, the azeotropic mixture of2-hydroxypropyl thioglyconate and of (2-hydroxy-1-methyl)ethylthioglycolate, mercaptoalkylaminoamides, N-mercaptoalkylalkanediamidesand formamidinesulfinic acid derivatives, salts thereof, and mixturesthereof.

Preferably, the reducing agent(s) are also chosen from salts such assodium sulfite, sodium dithionite or sodium thiosulfate, and mixturesthereof.

The chemical reducing agent(s) are advantageously applied in the form ofan aqueous solution of which the content of chemical reducing agents ispreferably between 0.01% and 10% by weight and more preferentiallybetween 0.1% and 5% by weight, relative to the total weight of theaqueous solution.

According to a preferred embodiment of the invention, the dyeing processdoes not use any reducing agent.

According to this preferred embodiment of the invention, the cosmeticcomposition comprising ingredients (a) and (b) does not comprise anyreducing agent.

The Cosmetic Medium and the Solvents

The triarylmethane dye(s) (a) chosen from the compounds of formula (I),as defined previously, and (b) the fluorescent dye(s), as definedpreviously, and also, when they are present, the oxidizing agent(s)and/or the reducing agent(s), may be dissolved beforehand before beingapplied to the keratin fibres.

In other words, the ingredients used in the dyeing process of thepresent invention may be present in one or more compositions.

The composition(s) comprising the ingredients according to the presentinvention are cosmetic compositions, i.e. they are preferably aqueous.Besides water, they may comprise one or more organic solvents, ormixtures thereof.

Examples of organic solvents that may be mentioned include linear orbranched C₂ to C₄ alkanols, such as ethanol and isopropanol; glycerol;polyols and polyol ethers, for instance 2-butoxyethanol, propyleneglycol, hexylene glycol, dipropylene glycol, propylene glycol monomethylether, diethylene glycol monomethyl ether and monoethyl ether, and alsoaromatic alcohols or ethers, for instance benzyl alcohol orphenoxyethanol, and mixtures thereof.

The pH

The pH of the composition(s) used in the dyeing process of the inventionand of the composition of the invention comprising ingredients (a) and(b) is preferably between 2 and 12 and more preferentially between 3 and11. It may be adjusted to the desired value by means of acidifying oralkaline agents usually used in the dyeing of keratin fibres, oralternatively using standard buffer systems.

The pH of the composition which comprises ingredients (a) and (b) andthat of the composition(s) used in the dyeing process of the inventionis preferably between 6 and 11 inclusive, more preferentially between 7and 10 and better still between 7.5 and 9.5, such as between 9 and 9.5.

Among the acidifying agents, mineral and organic acids as definedpreviously, mention may be made, by way of example, of mineral ororganic acids, for instance hydrochloric acid, orthophosphoric acid orsulfuric acid, carboxylic acids, for instance acetic acid, tartaricacid, citric acid and lactic acid, and sulfonic acids.

The alkaline agent(s) may be chosen especially from mineral, organic orhybrid alkaline agents, and mixtures thereof.

The mineral alkaline agent(s) are preferably chosen from ammonia,alkaline carbonates or bicarbonates such as ammonium, sodium orpotassium carbonate or bicarbonate, ammonium, sodium or potassiumhydroxide, or mixtures thereof.

The organic alkaline agent(s) are preferably chosen from organic amineswith a pK_(b) at 25° C. of less than 12, preferably of less than 10 andmore advantageously still of less than 6. It should be noted that itconcerns the pK_(b) corresponding to the function having the highestbasicity. In addition, the organic amines do not comprise any alkyl oralkenyl fatty chain comprising more than ten carbon atoms.

The organic alkaline agent(s) are preferably chosen from alkanolamines,in particular mono-, di- or tri-hydroxy(C₁-C₆)alkylamines, such astriethanolamine, oxyethylenated and/or oxypropylenated ethylenediamines,amino acids, polyamines of formula (XVII) below, and mixtures thereof:

in which formula (XVII) W is a divalent C₁-C₆ alkylene radicaloptionally substituted with one or more hydroxyl groups or a C₁-C₆ alkylradical, and/or optionally interrupted with one or more heteroatoms suchas O, or NR_(u); R_(x), R_(y), R_(z), R_(t) and R_(u), which may beidentical or different, represent a hydrogen atom or a C₁-C₆ alkyl,C₁-C₆ hydroxyalkyl or C₁-C₆ aminoalkyl radical.

Examples of amines of formula (XVII) that may be mentioned include1,3-diaminopropane, 1,3-diamino-2-propanol, spermine and spermidine.

The term “alkanolamine” is intended to mean an organic amine comprisinga primary, secondary or tertiary amine function, and one or more linearor branched C₁ to C₈ alkyl groups bearing one or more hydroxyl radicals.

Organic amines chosen from alkanolamines such as monoalkanolamines,dialkanolamines or trialkanolamines comprising one to three identical ordifferent C₁ to C₄ hydroxyalkyl radicals are in particular suitable forperforming the invention.

Among the compounds of this type, mention may be made ofmonoethanolamine (MEA), diethanolamine, triethanolamine,monoisopropanolamine, diisopropanolamine, N,N-dimethylethanolamine,2-amino-2-methyl-1-propanol, triisopropanolamine,2-amino-2-methyl-1,3-propanediol, 3-amino-1,2-propanediol,3-dimethylamino-1,2-propanediol and tris(hydroxymethyl)aminomethane.

More particularly, the amino acids that may be used are of natural orsynthetic origin, in their L, D or racemic form, and comprise at leastone acid function chosen more particularly from carboxylic acid,sulfonic acid, phosphonic acid and phosphoric acid functions. The aminoacids may be in neutral or ionic form.

As amino acids that may be used in the present invention, mention may bemade in particular of aspartic acid, glutamic acid, alanine, arginine,omithine, citrulline, asparagine, camitine, cysteine, glutamine,glycine, histidine, lysine, isoleucine, leucine, methionine,N-phenylalanine, proline, serine, taurine, threonine, tryptophan,tyrosine and valine.

Advantageously, the amino acids are basic amino acids comprising anadditional amine function optionally included in a ring or in a ureidofunction.

Such basic amino acids are preferably chosen from those corresponding toformula (XVIII) below, and also salts thereof:

R—CH₂—CH(NH₂)—C(O)—OH  (XVIII)

in which formula (XVIII) R represents a group chosen from imidazolyl,preferably imidazolyl-4-yl; aminopropyl; aminoethyl;—(CH₂)₂N(H)—C(O)—NH₂; and —(CH₂)₂—N(H)—C(NH)—NH₂.

The compounds corresponding to formula (XVIII) are histidine, lysine,arginine, omithine and citrulline.

The organic amine may also be chosen from organic amines of heterocyclictype. Besides histidine that has already been mentioned in the aminoacids, mention may in particular be made of pyridine, piperidine,imidazole, triazole, tetrazole and benzimidazole.

The organic amine may also be chosen from amino acid dipeptides. Asamino acid dipeptides that may be used in the present invention, mentionmay be made especially of camosine, anserine and balenine.

The organic amine may also be chosen from compounds comprising aguanidine function. As amines of this type that may be used in thepresent invention, besides arginine, which has already been mentioned asan amino acid, mention may be made in particular of creatine,creatinine, 1,1-dimethylguanidine, 1,1-diethylguanidine, glycocyamine,metformin, agmatine, n-amidinoalanine, 3-guanidinopropionic acid,4-guanidinobutyric acid and2-([amino(imino)methyl]amino)ethane-1-sulfonic acid.

Hybrid compounds that may be mentioned include the salts of the aminesmentioned previously with acids such as carbonic acid or hydrochloricacid.

Guanidine carbonate or monoethanolamine hydrochloride may be used inparticular.

Preferably, the alkaline agent(s) that are useful in the invention arechosen from aqueous ammonia, alkanolamines, amino acids in neutral orionic form, in particular basic amino acids, and preferablycorresponding to those of formula (XVIII).

More preferentially, the alkaline agent(s) are chosen from aqueousammonia, ammonium bicarbonate, ammonium hydroxide, mono-, di- ortri-hydroxy(C₁-C₆)alkylamines, such as triethanolamine, and mixturesthereof.

Forms of the Composition

The composition(s) comprising the triarylmethane dye(s) (a) chosen fromthe compounds of formula (I), as defined previously, and the fluorescentdye(s) (b) as defined previously, may be in various presentation forms,such as in the form of liquids, lotions, creams or gels or in any otherform that is suitable for dyeing keratin fibres.

It may also be packaged under pressure in an aerosol container in thepresence of a propellant or in a non-aerosol container and may form afoam.

Additives

When the ingredients used in the dyeing process according to the presentinvention are present in one or more composition(s), said compositionsmay also optionally comprise one or more additives, different from theingredients of the invention and among which mention may be made offatty substances, cationic, anionic, nonionic, amphoteric orzwitterionic surfactants, cationic, anionic, nonionic or amphotericpolymers or mixtures thereof, antidandruff agents, anti-seborrhoeaagents, agents for preventing hair loss and/or for promoting hairregrowth, vitamins and provitamins including panthenol, sunscreens,mineral or organic pigments, sequestrants, plasticizers, solubilizers,acidifying agents, mineral or organic thickeners, especially polymericthickeners, opacifiers or nacreous agents, antioxidants, hydroxy acids,fragrances, preserving agents, pigments and ceramides.

Needless to say, a person skilled in the art will take care to selectthis or these optional additional compound(s) such that the advantageousproperties intrinsically associated with the composition(s) inaccordance with the invention are not, or are not substantially,adversely affected by the envisaged addition(s).

The above additives may generally be present in an amount, for each ofthem, of between 0 and 20% by weight relative to the total weight of thecomposition comprising them.

The Dyeing Process

The process for dyeing keratin fibres according to the present inventioncomprises the application to said keratin fibres of the followingingredients:

(a) one or more triarylmethane dyes chosen from the compounds of formula(I), as defined previously, and also the optical isomers thereof, thegeometrical isomers thereof, the tautomers thereof, the organic ormineral acid or base salts thereof, the solvates thereof such ashydrates, and mixtures thereof, and(b) one or more fluorescent dyes, as defined previously,it being understood that the triarylmethane dye(s) (a) (ingredients (a))and the fluorescent dye(s) (ingredients (b)) are applied to said keratinfibres together or sequentially.

In other words, the dyeing process according to the present inventionmay be performed in one or more steps.

According to a particularly preferred embodiment, the triarylmethanedye(s) (a) and the fluorescent dye(s) (b), as defined previously, areapplied together (or jointly), i.e. simultaneously, to the keratinfibres. According to this embodiment, the dyeing process is performed inone step.

According to this one-step embodiment, the process comprises a step ofapplying to said keratin fibres a cosmetic composition according to theinvention which comprises one or more triarylmethane dyes (a) chosenfrom the compounds of formula (I), as defined previously, and also theoptical isomers thereof, the geometrical isomers thereof, the tautomersthereof, the organic or mineral acid or base salts thereof, the solvatesthereof such as hydrates, and mixtures thereof, and one or morefluorescent dyes (b) as defined previously.

According to another particularly preferred embodiment, thetriarylmethane dye(s) (a), as defined previously, and the fluorescentdye(s) (b), as defined previously, are applied sequentially, i.e.successively. According to this other embodiment, the dyeing process isperformed in at least two steps.

According to a first embodiment in at least two steps, the fluorescentdye(s) (b), as defined previously, are applied to the keratin fibressubsequently to the triarylmethane dye(s) (a), as defined previously. Inother words, the fluorescent dye(s) (b), as defined previously, areapplied after the triarylmethane dye(s) (a), as defined previously.

According to this first embodiment, the process for dyeing keratinfibres comprises at least the following two successive steps:

a first step of applying to said keratin fibres a cosmetic compositioncomprising one or more triarylmethane dyes (a) chosen from the compoundsof formula (I), as defined previously, and also the optical isomersthereof, the geometrical isomers thereof, the tautomers thereof, theorganic or mineral, acid or base salts thereof, the solvates thereofsuch as hydrates, and mixtures thereof, followed bya second step of applying to said keratin fibres a cosmetic compositionwhich comprises one or more fluorescent dyes (b), as defined previously.

According to a preferred embodiment in at least two steps, thetriarylmethane dye(s) (a), as defined previously, are applied to thekeratin fibres subsequently to the fluorescent dye(s) (b), as definedpreviously. In other words, the triarylmethane dye(s) (a), as definedpreviously, are applied after the fluorescent dye(s) (b), as definedpreviously.

According to this preferred embodiment, the process for dyeing keratinfibres comprises at least the following two successive steps:

a first step of applying to said keratin fibres a cosmetic compositioncomprising one or more fluorescent dyes (b), as defined previously,followed bya second step of applying to said keratin fibres a cosmetic compositioncomprising one or more triarylmethane dyes (a) chosen from the compoundsof formula (I), as defined previously, and also the optical isomersthereof, the geometrical isomers thereof, the tautomers thereof, theorganic or mineral, acid or base salts thereof, the solvates thereofsuch as hydrates, and mixtures thereof.

Preferably, ingredients (a) and (b) are applied to the keratin fibres ina bath ratio that may range from 0.1 to 10 and more particularly from0.2 to 8. For the purposes of the present invention, the term “bathratio” means the ratio between the total weight of ingredient (a) or (b)and the total weight of keratin fibres to be treated.

When the dyeing process is performed in one step, ingredients (a) and(b) are advantageously left to stand on the keratin fibres for a timeranging from 1 to 90 minutes and more preferentially for a time rangingfrom 5 to 60 minutes.

When the dyeing process is performed in at least two steps, each of theingredients (a) and (b) may be advantageously left to stand on thekeratin fibres for a time ranging from 1 to 60 minutes and morepreferentially for a time ranging from 5 to 45 minutes.

On conclusion of the dyeing process according to the invention, in oneor at least two steps, the keratin fibres are advantageously rinsed withwater. They may optionally be washed with a shampoo, followed by rinsingwith water, before being dried or left to dry.

When the dyeing process is performed in at least two steps, the keratinfibres are advantageously rinsed with water between each step. In otherwords, the dyeing process may comprise an intermediate rinsing stepbetween the application of the first ingredient and the application ofthe second ingredient. During this intermediate rinsing step, thekeratin fibres may optionally be washed with a shampoo, followed byrinsing with water, before being dried or left to dry.

The dyeing process according to the present invention may be performedat room temperature (25° C.) or with heating.

When they are present, the reducing agent(s) may be applied separatelyor together with one of the ingredients (a) or (b). Preferably, whenthey are present, the reducing agent(s) are applied together with theingredient (b).

When they are present, the oxidizing agent(s) may be applied separatelyor together with one of the ingredients (a) or (b). Preferably, whenthey are present, the oxidizing agent(s) are applied after applicationof ingredients (a) and (b).

According to a particular embodiment, the process for dyeing keratinfibres according to the present invention comprises the followingsuccessive steps:

a first step of applying to said keratin fibres a cosmetic compositioncomprising one or more triarylmethane dyes (a) chosen from the compoundsof formula (I), as defined previously, and also the optical isomersthereof, the geometrical isomers thereof, the tautomers thereof, theorganic or mineral, acid or base salts thereof, the solvates thereofsuch as hydrates, and mixtures thereof, followed bya second step of applying to said keratin fibres a cosmetic compositioncomprising one or more fluorescent dyes (b), as defined previously, andone or more reducing agents, as defined previously.

According to a particular embodiment of the dyeing process of theinvention, no step of said process involves an oxidizing agent.

According to another advantageous embodiment of the dyeing process ofthe invention, no step of said process involves a reducing agent.

The dyeing process according to the present invention may be applied towet or dry, preferably dry, keratin fibres.

The Multi-Compartment Device

The present invention also relates to a multi-compartment devicecomprising a first compartment containing one or more triarylmethanedyes (a) chosen from the compounds of formula (I), as definedpreviously, and also the optical isomers thereof, the geometricalisomers thereof, the tautomers thereof, the organic or mineral acid orbase salts thereof, the solvates thereof such as hydrates, and mixturesthereof, and a second compartment containing one or more fluorescentdyes (b) as defined previously.

Use

A subject of the present invention is also the use of one or morefluorescent dye(s) (b), as defined previously, combined with one or moretriarylmethane dye(s) (a) chosen from the compounds of formula (I), asdefined previously, and also the optical isomers thereof, thegeometrical isomers thereof, the tautomers thereof, the organic ormineral acid or base salts thereof, the solvates thereof such ashydrates, and mixtures thereof, for the dyeing of light keratin fibres,especially human keratin fibres such as the hair, in chestnut-brown,dark chestnut-brown, brown, brown with a glint or even black, withoutusing an additional dye other than (a) or (b).

According to a particular embodiment, the “keratin fibres” are humankeratin fibres and more particularly the hair.

The examples that follow serve to illustrate the invention without,however, being limiting in nature.

EXAMPLES

In the examples that follow, all the amounts are given as weightpercentages relative to the total weight of the composition, unlessotherwise indicated.

I. First Example of Combined Application a) Preparation of theCompositions

Composition (A1) comprising a triarylmethane dye of formula (I)according to the invention, was prepared from the ingredients whosecontents are mentioned in the table below.

Composition A1

0.2 Monoethanolamine pH = 4 Water qs 100

Compositions (B1) and (B2), comprising a fluorescent dye, were preparedfrom the ingredients whose contents are mentioned in the table below.

Composition B1 Composition B2

0.2 —

— 0.2 Monoethanolamine pH = 4 pH = 4 Water qs 100 qs 100

b) Procedure

Compositions (A1), (B1) and (B2) obtained above were mixed so as toobtain the following mixtures:

-   -   A1+B1 in a 1/1 ratio, and    -   A1+B2 in a 1/1 ratio.

10 ml of compositions (A1), (B1), (B2), (A1+B1) and (A1+B2) were appliedto 1 g locks of hair.

After a leave-on time of 20 minutes at room temperature, the locks ofhair were rinsed with water and wrung dry.

The locks were then subjected to 10 shampoo washes, made up of twocycles of five shampoo washes. After each shampoo wash cycle, the lockswere dried and the colour of the locks was measured using a MinoltaCM2600d spectrocolorimeter (specular components included, 10° angle,illuminant D65) in the CIEL*a*b* system.

In this system, L* represents the intensity of the colour, a* indicatesthe green/red colour axis and b* the blue/yellow colour axis.

The lower the value of L*, the darker or more intense the colour. Thehigher the value of a*, the redder the shade, and the higher the valueof b*, the yellower the shade.

c) Results

The results of the colouring on the locks of hair containing 90% whitehairs are given in the table below.

Colour L* a* b* Al Intense 40.50 −15.66 −15.51 blue B1 Red 40.68 51.7745.37 B2 Red 42.29 48.07 44.34 A1 + B1 Brown 20.29 5.88 5.05 A1 + B2Black 19.02 −0.28 −5.53

The results obtained above show that the simultaneous application of atriarylmethane dye of formula (I) according to the present invention andof a fluorescent dye makes it possible to obtain very intense andchromatic colours.

These results also show that the process according to the invention,using only two particular direct dyes, a triarylmethane dye of formula(I) combined with a fluorescent dye, makes it possible to obtain browncolours, which are persistent even after 10 shampoo washes.

II. Second Example of Combined Application

a) Preparation of the compositions

Composition (A2) comprising a triarylmethane dye of formula (I)according to the invention, was prepared from the ingredients whosecontents are mentioned in the table below.

Composition A2

0.2 Monoethanolamine pH = 9.5 Water qs 100

Compositions (B3) and (B4), comprising a fluorescent dye, were preparedfrom the ingredients whose contents are mentioned in the table below.

Composition B3 Composition B4

0.2 —

— 0.2 Monoethanolamine pH = 9.5 pH = 9.5 Water qs 100 qs 100

b) Procedure

Compositions (A2), (B3) and (B4) obtained above were mixed so as toobtain the following mixtures:

-   -   A2+B3 in a 1/1 ratio, and    -   A2+B4 in a 1/1 ratio.

10 ml of compositions (A2), (B3), (B4), (A2+B3) and (A2+B4) were appliedto 1 g locks of hair.

After a leave-on time of 20 minutes at room temperature, the locks ofhair were rinsed with water and wrung dry.

The locks were then subjected to 10 shampoo washes, made up of twocycles of five shampoo washes. After each shampoo wash cycle, the lockswere dried and the colour of the locks was measured using a MinoltaCM2600d spectrocolorimeter (specular components included, 10° angle,illuminant D65) in the CIEL*a*b* system.

In this system, L* represents the intensity of the colour, a* indicatesthe green/red colour axis and b* the blue/yellow colour axis.

The lower the value of L*, the darker or more intense the colour. Thehigher the value of a*, the redder the shade, and the higher the valueof b*, the yellower the shade.

c) Results

The results of the colouring on the locks of hair containing 90% whitehairs are given in the table below.

Colour L* a* b* A2 Intense blue 37.20 −13.47 −16.12 B3 Red 41.02 49.2344.44 B4 Red 38.42 46.87 38.15 A2 + B3 Brown with 18.66 9.75 13.69mahogany glints A2 + B4 Brown with 19.73 6.43 10.28 mahogany glints

The results obtained above show that the simultaneous application of atriarylmethane dye of formula (I) according to the present invention andof a fluorescent dye makes it possible to obtain very intense andchromatic colours.

These results also show that the process according to the invention,using only two particular direct dyes, a triarylmethane dye of formula(I) combined with a fluorescent dye, makes it possible to obtain browncolours, which are persistent even after 10 shampoo washes.

III. Comparative Example a) Preparation of the Compositions

Composition (A3) comprising a triarylmethane dye of formula (I)according to the invention, was prepared from the ingredients whosecontents are mentioned in the table below.

Composition A3

0.2 Monoethanolamine pH = 9.5 Water qs 100

Composition (B5), comprising a fluorescent dye as defined in the patentapplication EP 1 133 975, was prepared from the ingredients whosecontents are mentioned in the table below.

Composition B5

0.2 Monoethanolamine pH = 9.5 Water qs 100

b) Procedure

Compositions (A3) and (B5) obtained above were mixed so as to obtain themixture (A3+B5) in a 1/1 ratio.

10 ml of compositions (A3), (B5) and (A3+B5) were applied to 1 g locksof hair.

After a leave-on time of 20 minutes at room temperature, the locks ofhair were rinsed with water and wrung dry.

The locks were then subjected to one shampoo wash, and the colour of thelocks was measured using a Minolta CM2600d spectrocolorimeter (specularcomponents included, 10° angle, illuminant D65) in the CIEL*a*b* system.

In this system, L* represents the intensity of the colour, a* indicatesthe green/red colour axis and b* the blue/yellow colour axis.

The lower the value of L*, the darker or more intense the colour. Thehigher the value of a*, the redder the shade, and the higher the valueof b*, the yellower the shade.

c) Results

The results of the colouring on the locks of hair containing 90% whitehairs are given in the table below.

Colour L* a* b* A3 Intense 42.07 −8.33 −14.86 blue B5 Yellow 56.35 5.7166.38 A3 + B5 Green 40.68 −19.27 21.98

The results obtained above show that the association of a triarylmethanedye of formula (I) according to the present invention and of afluorescent dye, which is not chosen from cyanin, styryl/hemicyanin, andnaphthalimide dyes, is not able to provide brown colours.

IV. Third Example of Combined Application a) Preparation of theCompositions

Composition (A4) comprising a triarylmethane dye of formula (I)according to the invention, was prepared from the ingredients whosecontents are mentioned in the table below.

Composition A4

10⁻³ mol % Monoethanolamine pH = 9.5 Water qs 100

Compositions (B6) and (B7), comprising a fluorescent dye according tothe present invention, were prepared from the ingredients whose contentsare mentioned in the table below.

Composition B6 Composition B7

10⁻³ mol % —

— 10⁻³ mol % Monoethanolamine pH = 9.5 pH = 9.5 Water qs 100 qs 100

b) Procedure

Compositions (A4), (B6) and (B7) obtained above were mixed so as toobtain the following mixtures:

-   -   A4+B6 in a final concentration of 5*10⁴ mol %, and    -   A4+B7 in a final concentration of 5*10⁴ mol %.

10 ml of compositions (A4), (B6), (B7), (A4+B6) and (A4+B7) were appliedto 1 g locks of hair. Compositions (A4), (B6) and (B7) were also appliedin a final concentration of 5*10⁴ mol %.

After a leave-on time of 20 minutes at room temperature, the locks ofhair were rinsed with water and wrung dry.

The locks were then subjected to one shampoo wash, and the colour of thelocks was measured using a Minolta CM2600d spectrocolorimeter (specularcomponents included, 10° angle, illuminant D65) in the CIEL*a*b* system.

In this system, L* represents the intensity of the colour, a* indicatesthe green/red colour axis and b* the blue/yellow colour axis.

The lower the value of L*, the darker or more intense the colour. Thehigher the value of a*, the redder the shade, and the higher the valueof b*, the yellower the shade.

c) Results

The results of the colouring on the locks of hair containing 90% whitehairs are given in the table below.

Colour L* a* b* A4 Intense blue 34.58 −13.32 −22.83 B6 Red 39.51 51.0442.13 B7 Orange 44.21 40.41 42.88 A4 + B6 Brown 22.03 15.07 13.77 A4 +B7 Brown with 29.21 7.01 10.76 green glints

The results obtained above show that the simultaneous application of atriarylmethane dye of formula (I) according to the present invention andof a fluorescent dye, chosen from cyanin, styryl/hemicyanin, andnaphthalimide dyes, makes it possible to obtain very intense andchromatic colours.

These results also show that the process according to the invention,using only two particular direct dyes, a triarylmethane dye of formula(I) combined with a specific fluorescent dye, makes it possible toobtain brown colours, as well as brown with glints.

IV. Second Comparative Example of Combined Application a) Preparation ofthe Compositions

Composition (A5) comprising a triarylmethane dye of formula (I)according to the invention, was prepared from the ingredients whosecontents are mentioned in the table below.

Composition A5

10⁻³ mol % Monoethanolamine pH = 9.5 Water qs 100

Composition (B6), comprising a fluorescent dye according to the presentinvention, and composition (B8), comprising a fluorescent dye as definedin the patent application EP 1 133 975, were prepared from theingredients whose contents are mentioned in the table below.

Composition B6 Composition B8

10⁻³ mol % —

— 10⁻³ mol % Monoethanolamine pH = 9.5 pH = 9.5 Water qs 100 qs 100

b) Procedure

Compositions (A4), (B6) and (B8) obtained above were mixed so as toobtain the following mixtures:

-   -   A5+B6 in a final concentration of 5*10⁴ mol %, and    -   A5+B8 in a final concentration of 5*10⁴ mol %.

10 ml of compositions (A5), (B6), (B8), (A5+B6) and (A5+B8) were appliedto 1 g locks of hair. Compositions (A4), (B6) and (B8) were also appliedin a final concentration of 5* 10⁴ mol %.

After a leave-on time of 20 minutes at room temperature, the locks ofhair were rinsed with water and wrung dry.

The locks were then subjected to one shampoo wash, and the colour of thelocks was measured using a Minolta CM2600d spectrocolorimeter (specularcomponents included, 10° angle, illuminant D65) in the CIEL*a*b* system.

In this system, L* represents the intensity of the colour, a* indicatesthe green/red colour axis and b* the blue/yellow colour axis.

The lower the value of L*, the darker or more intense the colour. Thehigher the value of a*, the redder the shade, and the higher the valueof b*, the yellower the shade.

c) Results

The results of the colouring on the locks of hair containing 90% whitehairs are given in the table below.

Colour L* a* b* A5 Intense blue 41.45 −8.63 −13.11 B6 Red 39.51 51.0442.13 B8 Yellow 61.48 6.86 71.59 A5 + B6 Brown with 27.05 18.11 15.97mahogany glints A5 + B8 Green 36.03 −14.49 17.4

The results obtained above show that the simultaneous application of atriarylmethane dye of formula (I) according to the present invention andof a fluorescent dye, chosen from cyanin, styryl/hemicyanin, andnaphthalimide dyes (A5+B6), makes it possible to obtain very intense andchromatic colours.

These results also show that the process according to the invention,using only two particular direct dyes, a triarylmethane dye of formula(I) combined with a specific fluorescent dye, makes it possible toobtain brown colours.

In comparison, the association of a triarylmethane dye of formula (I)according to the present invention and of a fluorescent dye, which isnot chosen from cyanin, styryl/hemicyanin, and naphthalimide dyes(A5+B8), is not able to provide brown colours and provide only greenshades.

1. Process for dyeing keratin fibres, in particular human keratin fibressuch as the hair, comprising the application to said keratin fibres ofthe following ingredients: (a) one or more triarylmethane dyes chosenfrom the compounds of formula (I) below, the optical isomers thereof,the geometrical isomers thereof, the tautomers thereof, the organic ormineral, acid or base salts thereof, the solvates thereof such ashydrates, and mixtures thereof,

in which formula (I): R₁, R₂, R′₁ and R′₂, which may be identical ordifferent, represent: a hydrogen atom, a linear or branched C₁ to C₂₀alkyl radical; that is optionally substituted and/or optionallyinterrupted with one or more heteroatoms, preferably oxygen or sulfur,and/or with one or more groups comprising at least one heteroatom,preferably chosen from oxygen, sulfur, C(O), SO, SO₂ and SO₃ ⁻, orcombinations thereof, or a benzyl radical optionally substituted withone or more SO₃ ⁻ or SO₃H groups; R₃ and R′₃, which may be identical ordifferent, represent, independently of each other: a linear or branchedC₁ to C₆ alkyl radical; a sulfonate group SO₃ ⁻, or a sulfonic groupSO₃H; n and m, which may be identical or different, represent twointegers ranging from 0 to 4; the radicals R₄, which may be identical ordifferent, represent, independently of each other: a linear or branchedC₁ to C₆ alkyl radical; a hydroxyl radical, a group SO₃ ⁻, a group SO₃H,a halogen atom, preferably a chlorine atom, or alternatively twoadjacent radicals R₄ together form an unsaturated 6-membered ring,preferably an aromatic ring such as benzo, optionally substituted withone or more SO₃ ⁻ or SO₃H groups; q is an integer ranging from 0 to 4;R₅ represents: a hydrogen atom, a halogen atom, preferably a chlorineatom, an amino radical, a hydroxyl radical, an electron-withdrawinggroup SO₃ ⁻ or SO₃H, or a radical —NR₆R₇, in which R₆ and R₇, which maybe identical or different, represent, independently of each other: ahydrogen atom, or a linear or branched C₁ to C₆ alkyl radical; it beingunderstood that: the radical R₂ is present or absent, symbolized by thedashed bond, when R₂ is present, then the nitrogen atom that bears it isin cationic ammonium form, when R₂ is absent, then the nitrogen atomthat bears it is not charged, (+) is not present, and the compound offormula (I) optionally comprises one or more anions An⁻ and optionallyone or more cations M′ to ensure the electrical neutrality of themolecule; with: An⁻ representing an anion, preferably chosen frombromide, chloride, methylsulfate and toluenesulfonate ions or a mixtureof these ions; and M⁺ representing a cation, preferably chosen fromsodium, potassium, magnesium, calcium, zinc and ammonium ions or amixture of these ions; and (b) one or more fluorescent dyes; saidfluorescent dyes being direct dyes chosen from cyanin dyes,styryl/hemicyanin dyes, naphthalimide dyes, and mixtures thereof; itbeing understood that the triarylmethane dye(s) (a) and the fluorescentdye(s) (b) are applied to said keratin fibres together or sequentially.2. Process according to claim 1, characterized in that n and m, whichmay be identical or different, represent two integers ranging from 0 to2.
 3. Process according to claim 1, characterized in that R₁, R₂, R′₁and R′₂, which may be identical or different, represent, independentlyof each other: 290 a hydrogen atom, a linear or branched C₁ to C₆ alkylradical, which is optionally substituted, and/or optionally interruptedwith one or more heteroatoms chosen from oxygen and sulfur, and/or withone or more groups comprising at least one heteroatom, preferably chosenfrom oxygen, sulfur, C(O), SO, SO₂ and SO₃ ⁻, or combinations thereof,preferably an unsubstituted linear or branched C₁ to C₆ alkyl radical,and more preferentially an unsubstituted linear or branched C₁ to C₄alkyl radical, or a benzyl radical substituted with an SO₃ ⁻ group. 4.Process according to claim 1, characterized in that R₅ represents: ahydrogen atom, an SO₃ ⁻ group, or a radical —NR₆R₇, with R₆ and R₇,which may be identical or different, representing, independently of eachother, a hydrogen atom or a linear or branched C₁ to C₆ alkyl radical,and preferably a C₁ to C₄ alkyl radical, such as a methyl or ethylradical.
 5. Process according to claim 1, characterized in that thetriarylmethane dye(s) are cationic and are chosen from the compounds offormula (I-cat) below:

in which formula (I-cat): R₁, R₂, R′₁ and R′₂, which may be identical ordifferent, represent: a hydrogen atom, a linear or branched C₁ to C₂₀alkyl radical: that is optionally substituted and/or optionallyinterrupted with one or more heteroatoms, preferably oxygen or sulfur,and/or with one or more groups comprising at least one heteroatom,preferably chosen from oxygen, sulfur, C(O), SO, SO₂ and SO₃ ⁻, orcombinations thereof, or a benzyl radical optionally substituted withone or more SO₃ ⁻ or SO₃H groups: R₃ and R′₃, which may be identical ordifferent, represent, independently of each other: a linear or branchedC₁ to C₆ alkyl radical: a sulfonate group SO₃ ⁻, or a sulfonic groupSO₃H: n and m, which may be identical or different, represent twointegers ranging from 0 to 4; the radicals R₄, which may be identical ordifferent, represent, independently of each other: a linear or branchedC₁ to C₆ alkyl radical: a hydroxyl radical, a group SO₃ ⁻; a group SO₃H,a halogen atom, preferably a chlorine atom, or alternatively twoadjacent radicals R₄ together form an unsaturated 6-membered ring,preferably an aromatic ring such as benzo, optionally substituted withone or more SO₃ ⁻ or SO₃H groups: q is an integer ranging from 0 to 4:R₅ represents: a hydrogen atom, a halogen atom, preferably a chlorineatom, an amino radical, a hydroxyl radical, an electron-withdrawinggroup SO₃ ⁻ or SO₃H, or a radical —NR₆R₇, in which R₆ and R₇, which maybe identical or different, represent, independently of each other: ahydrogen atom, or a linear or branched C₁ to C₆ alkyl radical: it beingunderstood that: the radical R₂ is present or absent, symbolized by thedashed bond, when R₂ is present, then the nitrogen atom that bears it isin cationic ammonium form, when R₂ is absent, then the nitrogen atomthat bears it is not charged, (+) is not present, and it beingunderstood that (I-cat) does not comprise more than one sulfonate group.6. Process according claim 1, characterized in that the triarylmethanedye(s) are anionic and are chosen from the compounds of formula (I-an′)or (I-an″) below:

in which formula (I-an′) or (I-an″): R₁, R₂, R′₁ and R′₂, which may beidentical or different, represent: a hydrogen atom, a linear or branchedC₁ to C₂₀ alkyl radical: that is optionally substituted and/oroptionally interrupted with one or more heteroatoms, preferably oxygenor sulfur, and/or with one or more groups comprising at least oneheteroatom, preferably chosen from oxygen, sulfur, C(O), SO, SO₂, andSO₃ ⁻, or combinations thereof, or a benzyl radical optionallysubstituted with one or more SO₃ ⁻ or SO₃H groups: R₃ and R′₃, which maybe identical or different, represent, independently of each other: alinear or branched C₁ to C₆ alkyl radical: a sulfonate group SO₃ ⁻, or asulfonic group SO₃H: n and m, which may be identical or different,represent two integers ranging from 0 to 4: the radicals R₄, which maybe identical or different, represent, independently of each other: alinear or branched C₁ to C₆ alkyl radical: a hydroxyl radical, a groupSO₃ ⁻, a group SO₃H, a halogen atom, preferably a chlorine atom, oralternatively two adjacent radicals R₄ together form an unsaturated6-membered ring, preferably an aromatic ring such as benzo, optionallysubstituted with one or more SO₃ ⁻ or SO₃H groups: q is an integerranging from 0 to 4: R₅ represents: a hydrogen atom, a halogen atom,preferably a chlorine atom, an amino radical, a hydroxyl radical, anelectron-withdrawing group SO₃ ⁻ or SO₃H, or a radical —NR₆R₇, in whichR₆ and R₇, which may be identical or different, represent, independentlyof each other: a hydrogen atom, or a linear or branched C₁ to C₆ alkylradical: it being understood that: the radical R₂ is present or absent,symbolized by the dashed bond, when R₂ is present, then the nitrogenatom that bears it is in cationic ammonium form, when R₂ is absent, thenthe nitrogen atom that bears it is not charged, (+) is not present, andit being understood that: (I-an′) comprises at least two sulfonategroups on ring A, B or C, (I-an″) comprises at least one sulfonate groupon ring A, B or C, and one or more cation(s) M⁺ are present tocompensate for the anionic charge(s) of the sulfonate group(s), whereinM⁺ is chosen from sodium, potassium, magnesium, calcium, zinc, andammonium ions, or a mixture of these ions.
 7. Process according to anyone of claim 1, characterized in that the triarylmethane dye(s) arenonionic and are chosen from the compounds of formula (I-nion) below:

in which formula (I-nion): R₁, R₂, R′₁ and R′₂, which may be identicalor different, represent: a hydrogen atom, a linear or branched C₁ to C₂₀alkyl radical: that is optionally substituted and/or optionallyinterrupted with one or more heteroatoms, preferably oxygen or sulfur,and/or with one or more groups comprising at least one heteroatom,preferably chosen from oxygen, sulfur, C(O), SO, SO₂ and SO₃ ⁻, orcombinations thereof, or a benzyl radical optionally substituted withone or more SO₃ ⁻ or SO₃H groups: R₃ and R′₃, which may be identical ordifferent, represent, independently of each other: a linear or branchedC₁ to C₆ alkyl radical: a sulfonate group SO₃ ⁻, or a sulfonic groupSO₃H: n and m, which may be identical or different, represent twointegers ranging from 0 to 4: the radicals R₄, which may be identical ordifferent, represent, independently of each other: a linear or branchedC₁ to C₆ alkyl radical: a hydroxyl radical, a group SO₃ ⁻, a group SO₃H,a halogen atom, preferably a chlorine atom, or alternatively twoadjacent radicals RP together form an unsaturated 6-membered ring,preferably an aromatic ring such as benzo, optionally substituted withone or more SO₃ ⁻ or SO₃H groups: q is an integer ranging from 0 to 4:R₅ represents: a hydrogen atom, a halogen atom, preferably a chlorineatom, an amino radical, a hydroxyl radical, an electron-withdrawinggroup SO₃ ⁻ or SO₃H, or a radical —NR₆R₇, in which R₆ and R₇, which maybe identical or different represent, independently of each other: ahydrogen atom, or a linear or branched C₁ to C₆ alkyl radical: it beingunderstood that: the radical R₂ is present or absent, symbolized by thedashed bond, when R₂ is present, then the nitrogen atom that bears it isin cationic ammonium form, when R₂ is absent, then the nitrogen atomthat bears it is not charged, (+) is not present, and it beingunderstood that (I-nion) does not comprise any sulfonate groups on ringA, B or C.
 8. Process according to claim 1, characterized in that thetriarylmethane dye(s) (a) are chosen from the following compounds, theoptical isomers thereof, the geometrical isomers thereof, the tautomersthereof, the organic or mineral, acid or base salts thereof, thesolvates thereof such as hydrates, and mixtures thereof:


9. Process according to claim 1, characterized in that the fluorescentdye(s) (b) are direct and cationic and are chosen from styryl orhemicyanin cationic dyes.
 10. Process according to claim 1,characterized in that the fluorescent dye(s) (b) are dyes which absorblight in the yellow, orange and red range, preferably in the absorptionwavelength λ_(abs) between 400 nm and 500 nm inclusive.
 11. Processaccording to claim 1, characterized in that the fluorescent dye(s) (b)are dyes which bear at least one cationic chromophore chosen fromformulae (III), (IV), (IIIa) and (IVa) below:W⁺—[C(R^(c))═C(R^(d))]_(m′)—Ar′-(*)Q⁻  (III)Ar—[C(R^(d))═C(R^(c))]_(m′)—W′⁺-(*)Q⁻  (IV), in which formulae (III) and(IV): W⁺ represents a cationic heteroaryl group, in particularcomprising a quaternary ammonium optionally substituted with one or more(C₁-C₈)alkyl groups optionally substituted in particular with one ormore hydroxyl groups; W′⁺ represents a divalent heteroaryl radical asdefined for W⁺; Ar represents an aryl group such as phenyl or naphthyl,optionally substituted preferably with i) one or more halogen atoms suchas chlorine or fluorine; ii) one or more (C₁-C₈)alkyl and preferablyC₁-C₄ alkyl groups such as methyl; iii) one or more hydroxyl groups; iv)one or more (C₁-C₈)alkoxy groups such as methoxy; v) one or morehydroxy(C₁-C₈)alkyl groups such as hydroxyethyl, vi) one or more aminoor (di)(C₁-C₈)alkylamino groups, preferably with the C₁-C₄ alkyl partoptionally substituted with one or more hydroxyl groups, such as(di)hydroxyethylamino, vii) with one or more acylamino groups; viii) oneor more heterocycloalkyl groups such as piperazinyl, piperidyl or 5- or6-membered heteroaryl such as pyrrolidinyl, pyridyl and imidazolinyl;Ar′ is a divalent aryl radical as defined for Ar; m′ represents aninteger between 1 and 4 inclusive, in particular, m′ is 1 or 2; betterstill 1; R^(c) and R^(d), which may be identical or different, representa hydrogen atom or optionally a substituted (C₁-C₈)alkyl and preferablyC₁-C₄ alkyl group, or alternatively R^(c) is contiguous with W or W⁺and/or R^(d) is contiguous with Ar or Ar′ and form, with the atoms thatbear them, a (hetero)cycloalkyl; in particular, R^(c) is contiguous withW⁺ or W′⁺ and forms a (hetero)cycloalkyl such as cyclohexyl; Q⁻ is anorganic or mineral anionic counterion; (*) represents the part of thefluorescent chromophore that is bonded to the rest of the dye;preferably, W⁺ or W′⁺ is an imidazolium, pyridinium, benzimidazolium,pyrazolium, benzothiazolium or quinolinium radical optionallysubstituted with one or more identical or different C₁-C₄ alkylradicals; preferably, the fluorescent chromophore(s) are chosen fromthose with m′=1, Ar representing a phenyl group substituted para to thestyryl group —C(R^(d))═C(R^(c))— with a (di)(hydroxy)(C₁-C₆)(alkyl)aminogroup such as dihydroxy(C₁-C₄)alkylamino, and W′⁺ representing animidazolium or pyridinium group, preferably ortho- or para-pyridinium;

where

represents the bond with the dye in which formulae (IIIa) and (IVa)R^(e), R^(f), R^(g) and R^(h), which may be identical or different,represent a hydrogen atom or a (C₁-C₆)alkyl group which is optionallysubstituted, preferentially with a di(C₁-C₆)alkylamino ortri(C₁-C₆)alkylammonium group such as trimethylammonium.
 12. Processaccording to claim 1, characterized in that the fluorescent dye(s) (b)are chosen from the dyes of formulae (V), (VI) and (VII) and also theorganic or mineral acid or base salts thereof, the optical isomers,geometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates:

in which formulae (V), (VI) and (VII): R₁ and R₂, which may be identicalor different, represent a hydrogen atom or a C₁-C₆ alkyl group;preferentially a hydrogen atom; G₁ represents a hydrogen atom or a groupchosen from NH₂ and OH; R_(a), R′_(a), R″_(a), R′″_(a), R_(b), R′_(b),R″_(b) and R′″_(b), which may be identical or different, represent a) ahydrogen atom, b) a halogen atom, a group from among: c) amino, d)(C₁-C₄)alkylamino, e) (C₁-C₄)dialkylamino, f) cyano, g) carboxyl —C(O)OHor carboxylate —C(O)O⁻, Q⁺, h) hydroxyl —OH or alkoxide —O⁻Q⁺, i)(poly)halo(C₁-C₆)alkyl such as trifluoromethyl, j) acylamino, k)(C₁-C₆)alkoxy, l) (C₁-C₆)alkylthio, m) (poly)hydroxy(C₂-C₄)alkoxy, n)(C₁-C₆)alkylcarbonyloxy, o) (C₁-C₆)alkoxycarbonyl, p)(C₁-C₆)alkylcarbonylamino, q) acylamino, r) carbamoyl, s)(C₁-C₆)alkylsulfonylamino, t) aminosulfonyl, u) —SO₃H or sulfonate —SO₃⁻, Q⁺ or v) (C₁-C₆)alkyl optionally substituted with a group chosen from(C₁-C₆)alkoxy, hydroxyl, cyano, carboxyl, amino, (di)(C₁-C₄)alkylamino,or alternatively the two alkyl radicals borne by the nitrogen atom ofthe amino group form a 5- to 7-membered heterocycle optionallycomprising another nitrogen or non-nitrogen heteroatom; in particular,R_(a), R′_(a), R″_(a), R′41 _(a), R_(b), R′_(b), R″_(b) and R′41 _(b)represent a hydrogen or halogen atom or a (C₁-C₄)alkyl group, preferablya hydrogen atom; or alternatively two groups R_(a) and R′_(a); R_(b) andR′_(b) borne by two adjacent carbon atoms together form a benzo orindeno ring, a fused heterocycloalkyl or fused heteroaryl group; thebenzo, indeno, heterocycloalkyl or heteroaryl ring being optionallysubstituted with a halogen atom, an amino, (C₁-C₄)alkylamino,(C₁-C₄)dialkylamino, nitro, cyano, carboxyl, hydroxyl or trifluoromethylgroup, an acylamino, (C₁-C₄)alkoxy (poly)hydroxy(C₁-C₄)alkoxy,(C₁-C₄)alkylcarbonyloxy, (C₁-C₄)alkoxycarbonyl or(C₁-C₄)alkylcarbonylamino radical, an acylamino, carbamoyl oralkoxyalkylsulfonylamino radical, an aminosulfonyl radical, or a(C₁-C₆)alkyl radical optionally substituted with: a group chosen from(C₁-C₆)alkoxy, hydroxyl, cyano, carboxyl, amino, (C₁-C₄)alkylamino and(C₁-C₄)dialkylamino, or alternatively the two alkyl radicals borne bythe nitrogen atom of the amino group form a 5- to 7-membered heterocycleoptionally comprising another nitrogen or non-nitrogen heteroatom;preferentially, R_(a) and R′_(a) together form a benzo group; oralternatively, two groups R_(i) and R_(a); and/or a group R′_(i) andR′_(a) together form a fused (hetero)cycloalkyl, preferentiallycycloalkyl such as cyclohexyl; R_(g) represents a hydrogen atom, a(hetero)aryl(C₁-C₄)alkyl group or a (C₁-C₆)alkyl group that isoptionally substituted; preferentially, R_(b) represents a hydrogen atomor a (C₁-C₃)alkyl or benzyl group; R_(e) represents a covalent bond, alinear or branched, optionally substituted (C₁-C₈)alkylene or(C₂-C₈)alkenylene hydrocarbon-based chain, preferably R_(e) representsan unsubstituted (C₁-C₆)alkylene; R_(f) represents a hydrogen atom, a(C₁-C₄)alkoxy group, an amino group R₃R₄N—, a quaternary ammonium groupM′, R₃R₄R₅N⁺— in which R₃, R₄ and R₅, which may be identical ordifferent, represent a (C₁-C₄)alkyl group or R₃R₄N— represents anoptionally substituted heteroaryl group, preferentially an optionallysubstituted imidazolyl group, or alternatively M′, R₃R₄R₅N⁺— representsan optionally substituted cationic heteroaryl group, preferentially animidazolinium group optionally substituted with a (C₁-C₃)alkyl group; Grepresents i) a group —NR_(c)R_(d), ii) —OR with R representing a) ahydrogen atom, b) an optionally substituted, preferentiallyunsubstituted (C₁-C₆)alkyl group, c) an optionally substituted(hetero)aryl group, d) an optionally substituted(hetero)aryl(C₁-C₆)alkyl group such as benzyl, e) optionally substituted(hetero)cycloalkyl, f) optionally substituted(hetero)cycloalkyl(C₁-C₆)alkyl; according to a particular embodiment, Grepresents a group —NR_(c)R_(d), according to another particularembodiment, G represents a (C₁-C₆)alkoxy group; or alternatively when Grepresents —NR_(c)R_(d), two groups R_(c) and R′_(a) and/or R_(d) andR_(a) together form a saturated heteroaryl or heterocycle, optionallysubstituted with one or more (C₁-C₆)alkyl groups, preferentially a 5- to7-membered heterocycle containing one or two heteroatoms chosen fromnitrogen and oxygen; more preferentially, the heterocycle is chosen frommorpholinyl, piperazinyl, piperidyl and pyrrolidinyl groups; R_(c) andR_(d), which may be identical or different, represent a hydrogen atom ora group from among: a) optionally substituted (hetero)aryl such asphenyl, b) optionally substituted (hetero)aryl(C₁-C₄)alkyl, c)optionally substituted (hetero)cycloalkyl, d) optionally substituted(hetero)cycloalkyl(C₁-C₄)alkyl, f) (C₂-C₈)alkyl or g) (C₁-C₈)alkyl whichis optionally substituted, preferably optionally substituted with ahydroxyl, carboxyl, carboxylate, sulfate or sulfonate group; oralternatively two adjacent radicals R_(c) and R_(d) borne by the samenitrogen atom together form an optionally substituted heterocyclic oroptionally substituted heteroaryl group; R_(i) and R′_(i), which may beidentical or different, represent a hydrogen atom or a (C₁-C₄)alkylgroup;

represents a (hetero)aryl group fused to the phenyl ring; oralternatively is absent from the phenyl; preferentially, when the ringis present, the ring is a benzo; m represents an integer between 1 and18 inclusive, particularly an integer between 1 and 14 inclusive;preferentially an integer between 2 and 10 inclusive; morepreferentially an integer between 3 and 8; more particularly an integerbetween 4 and 6; M′ represents an anionic counterion, derived from asalt of an organic or mineral acid, or from an organic or mineral basethat ensures the electrical neutrality of the dye; Q⁺ represents acationic counterion, derived from a salt of an organic or mineral acid,or from an organic or mineral base that ensures the electricalneutrality of the dye such as alkali metal, alkaline-earth metal orammonium; it being understood that when the dye comprises a carboxylate,sulfonate or alkoxide group, then M′ and Q⁺ may be absent to ensure theelectrical neutrality of said dye.
 13. Process according to claim 1,characterized in that the fluorescent dye(s) (b) are chosen from thestyryl dyes of formula (VIII) below, and also the organic or mineralacid or base salts thereof, the optical isomers, geometrical isomers andtautomers thereof, and the solvates thereof such as hydrates:

in which formula (VIII) R₁ and R₂, which may be identical or different,represent a hydrogen atom; R_(i) and R′_(i), which may be identical ordifferent, represent a hydrogen atom or a (C₁-C₄)alkyl group, preferablyhydrogen; R_(a), R′_(a) and R″_(a), which may be identical or different,represent a hydrogen atom, a halogen atom such as fluorine, or an —OH,—O⁻Q⁺, (C₁-C₆)alkoxy, nitro, or cyano group, with Q⁺ representing acationic counterion, derived from a salt of an organic or mineral acid,or from an organic or mineral base that ensures the electricalneutrality of the dye such as alkali metal, alkaline-earth metal orammonium; R_(b), R′_(b) and R″_(b), which may be identical or different,represent a hydrogen atom or a (C₁-C₆)alkyl group; or alternatively twocontiguous radicals R_(b) and R′_(b) form, together with the carbonatoms that bear them, a benzo group that is condensed or fused to thepyridinium group, said benzo group possibly being substituted;preferably, said benzo group is unsubstituted; G represents a group—NR_(c)R_(d) or (C₁-C₆)alkoxy group which is optionally substituted,preferentially unsubstituted; according to a particular embodiment, Grepresents a group —NR_(c)R_(d), according to another particularembodiment, G represents a (C₁-C₆)alkoxy group; R_(i) and R′_(i), whichmay be identical or different, represent a hydrogen atom or a(C₁-C₄)alkyl group;

represents an aryl or heteroaryl group fused to the phenyl ring; oralternatively is absent from the phenyl ring; preferentially, when thering is present, the ring is a benzo; m represents an integer between 1and 18 inclusive; particularly an integer between 2 and 16 inclusive;preferentially an integer between 3 and 10; more preferentially aninteger between 4 and 6; R_(c) and R_(d), which may be identical ordifferent, represent a hydrogen atom, a (C₂-C₄)alkyl group or asubstituted (C₁-C₈)alkyl group, preferably (C₂-C₄)alkyl substituted inparticular with one or more groups chosen from i) cyano, ii)(C₁-C₃)alkoxy, iii) hydroxyl and iv) (C₁-C₃)alkylcarbonyl, preferablywith one or more hydroxyl groups; and M′ representing an anioniccounterion, derived from a salt of an organic or mineral acid, or froman organic or mineral base that ensures the electrical neutrality of thedye; it being understood that when the dye comprises an alkoxide group,then M′ and Q⁺ may be absent to ensure the electrical neutrality of saiddye.
 14. Process according to claim 1, characterized in that thefluorescent dye(s) (b) are chosen from the styryl dyes of formula (IX)below, and also the organic or mineral acid or base salts thereof, theoptical isomers, geometrical isomers and tautomers thereof, and thesolvates thereof such as hydrates:

in which formula (IX) G represents a group —NR_(c)R_(d) or (C₁-C₆)alkoxygroup which is optionally substituted, preferentially unsubstituted:according to a particular embodiment, G represents a group —NR_(c)R_(d),according to another particular embodiment, G represents a (C₁-C₆)alkoxygroup; G₁ represents a hydrogen atom or a group chosen from NH₂ and OH:R_(a), and R′_(a), which may be identical or different, represent ahydrogen atom, a halogen atom such as fluorine, or an —OH, —O⁻Q⁺,(C₁-C₆)alkoxy, nitro, or cyano group, wherein Q⁺ represents a cationiccounterion, derived from a salt of an organic or mineral acid, or froman organic or mineral base that ensures the electrical neutrality of thedye such as alkali metal, alkaline-earth metal or ammonium; R_(b), andR′_(b), which may be identical or different, represent a hydrogen atomor a (C₁-C₆)alkyl group: and m represents an integer between 1 and 18inclusive: particularly an integer between 2 and 16 inclusive:preferentially an integer between 3 and 10: more preferentially aninteger between 4 and
 6. 15. Process according to claim 1, characterizedin that the fluorescent dye(s) (b) are chosen from the compounds offormulae (X), (XI), (XII) and (XIII) below, and also the organic ormineral acid or base salts thereof, the optical isomers, geometricalisomers and tautomers thereof, and the solvates thereof such ashydrates:

in which formulae (X), (XI), (XII) and (XIII): R¹, R², R³ and R⁴, whichmay be identical or different, represent a hydrogen atom or a(C₁-C₆)alkyl group; preferably, R² and R³ represent a hydrogen atom andR¹ and R⁴, which may be identical or different, represent a hydrogenatom or a (C₁-C₄)alkyl group; R⁵, R⁶, R⁷, R⁸ and R⁹, which may beidentical or different, represent i) a hydrogen atom or ii) a halogenatom such as Cl, Br or F, iii) a group OR in which R represents ahydrogen atom or Q⁺, or a (C₁-C₃)alkyl group, a group from among iv)aryl such as benzene, v) aryl(C₁-C₃)alkyl such as benzyl, vi) cyano,vii) nitro, viii) (C₁-C₃)alkylthio, ix) amino NR¹⁰R¹¹ with R¹⁰ and R¹¹,which may be identical or different, representing a) a hydrogen atom, b)a (C₂-C₄)alkyl group or c) a substituted (C₁-C₈)alkyl group, preferably(C₂-C₄)alkyl optionally substituted with one or more groups chosen from:cyano, (C₁-C₃)alkoxy, hydroxyl, and (C₁-C₃)alkylcarbonyl; in particular,R¹⁰ and R¹¹, which may be identical or different, represent a hydrogenatom or a (C₁-C₆)alkyl group substituted with one or more hydroxyl,cyano or (C₁-C₃)alkylcarbonyl groups such as hydroxyethyl; m representsan integer between 1 and 18 inclusive; particularly an integer between 2and 16 inclusive; preferentially an integer between 3 and 10; morepreferentially an integer between 4 and 6; M′ represents an anioniccounterion derived from a salt of an organic or mineral acid, or from anorganic or mineral base that ensures the electrical neutrality of thedye; and Q⁺ represents a cationic counterion, derived from a salt of anorganic or mineral acid, or from an organic or mineral base that ensuresthe electrical neutrality of the dye such as alkali metal,alkaline-earth metal or ammonium; it being understood that when the dyecomprises an alkoxide group, then M′ and Q⁺ may be absent to ensure theelectrical neutrality of said dye.
 16. Process according to claim 15,characterized in that the fluorescent dye(s) (b) of the invention arechosen from those of formulae (XIV) and (XV) below:

in which formulae (XIV) and (XV) R⁵, R⁷, R⁸ and m are: R⁵ and R⁸, whichmay be identical or different, represent a hydrogen atom or a(C₁-C₄)alkoxy group such as methoxy, preferably, R⁵ and R⁸ represent ahydrogen atom; R⁷ represents a (C₁-C₄)alkoxy group or NR¹⁰R¹¹ with R¹⁰and R¹¹, which may be identical or different, representing a) a hydrogenatom, or b) a (C₁-C₈)alkyl group optionally substituted with one or moregroups chosen from i) hydroxyl, ii) R—Z—C(X)—Y— with X, Y and Zrepresenting an oxygen or sulfur atom or N(R′), or alternatively Xand/or Z represent a bond, R and R′, which may be identical ordifferent, represent a hydrogen atom or a (C₁-C₆)alkyl group,preferably, X represents an oxygen atom, iii) sulfonic SO₃H, iv)sulfonate SO₃ ⁻, Q⁺, v) carboxylate C(O)O⁻, Q⁺ with Q⁺ representing acationic counterion such as an alkali metal or alkaline-earth metal; inparticular, R⁷ represents a group NR¹⁰R¹¹ with R¹⁰ and R¹¹, which may beidentical or different, representing a) a hydrogen atom, or b) a(C₁-C₆)alkyl group optionally substituted with one or more groups chosenfrom i) hydroxyl, ii) carboxyl, iii) carboxylate, iv) sulfonic, and v)sulfonate, more particularly chosen from identical or different groupsrepresenting a) a hydrogen atom, or b) a (C₁-C₆)alkyl group optionallysubstituted with one or more groups chosen from i) hydroxyl, ii)carboxyl, and iii) carboxylate; m represents an integer between 1 and 18inclusive; particularly an integer between 1 and 6 inclusive;preferentially an integer between 1 and 4; more preferentially aninteger between 1 and 2; and M′ represents an anionic counterion,derived from a salt of an organic or mineral acid, or from an organic ormineral base that ensures the electrical neutrality of the dye; it beingunderstood that when the dye comprises an alkoxide group, then M′ and Q⁺may be absent to ensure the electrical neutrality of said dye. 17.Process according to claim 15, characterized in that the fluorescentdye(s) (b) are chosen from: the fluorescent dyes of formula (X) with: R¹R² R³ R⁴ R⁵ R⁶ R⁷ R⁸ R⁹ m H H H H H H H H H 1 H H H H H t-Bu OH t-Bu H 5H H H H H t-Bu OH t-Bu H 5 H H H H H H NH₂ H H 1 H H H H H H NH₂ H OCH₃1 H H H H H H OH Br H 5 H H H H H OCH₃ OH OCH₃ H 5 H H H H Cl H OH H Cl5 H H H H H H OH H H 10 H H H H H OCH₃ OH OCH₃ H 10 H H H H H t-Bu OHt-Bu H 10 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H HH H H H N(CH₂CH₃)₂ H H 1 H H H H H t-Bu OH t-Bu H 10 H H H H H HN(CH₂CH₃)CH₂CH₂OH H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H HN(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H HN(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H 1 H H H H H H N(CH₂CH₃)₂ H H1 H H H H H H n-C₆H₁₃ H H 1 H H H H H H N(CH₂CH₂OH)₂ H H 2 H H H H H HN(n-Bu)₂ H H 2 H H H H H OCH₃ OH H H 10 H H H H H H OC₂H₅OH H H 1 H H HH H H OH H H 1 H H benzo H H H H H 1 H H benzo H H N(CH₂CH₂OH)₂ H H 1 HH benzo H H N(CH₂CH₂OH)₂ H H 1

and also the organic or mineral acid or base salts thereof, the opticalisomers, geometrical isomers and tautomers thereof, and the solvatesthereof such as hydrates; the fluorescent dyes of formula (XI) with: R¹R² R³ R⁴ R⁵ R⁶ R⁷ R⁸ R⁹ m CH₃ H H H OH H OCH₃ H H 2 CH₃ H H H H H OCH₃OCH₂-Ph H 2 CH₃ H H H H H H H OCH₃ 2 CH₃ H H H F H H H H 2 CH₃ H H H H HH OPh H 2 CH₃ H H H H H N(CH₂CH₂OAc)₂ H H 2 CH₃ H H H OCH₃ H OCH₃ OCH₃ H2 CH₃ H H H H H H CH₃ H 2 CH₃ H H H H H OH H H 2 CH₃ H H H H OCH₃ OCH₃OCH₃ H 2 CH₃ H H H H OCH₃ OH OH H 2 CH₃ H H H H H OCH₃ OCH₃ OCH₃ 2 CH₃ HH H H H H OCH₃ OH 2 CH₃ H H H H H N(n-butyl)₂ H H 2 CH₃ H H H H OCH₃OCH₃ H H 2 CH₃ H H H H H H H H 2 CH₃ H H H H H i-propyl H H 2 H H H H HH OH H H 6 H H H H H OCH₃ OCH₃ OCH₃ H 6 H H H H OH H OCH₃ H H 2 H H H HOCH₃ H H OCH₃ OCH₃ 2 H H H H H H H H Br 2 H H H H H H OH H H 2 H H H HOCH₃ OCH₃ OCH₃ H H 6 H H H H OH OCH₃ H H H 6 H H H H H OCH₃ OCH₃ H H 6 HH H H H OCH₃ OCH₃ H H 2 H H H H H H C(O)—OH H H 6 H H H H H H C(O)—OH HH 2 H H H H H H i-propyl H H 2 H H H H H H N(CH₃)CH₂CH₂CN H H 2 H H H HH H OCH₃ OCH₂Ph H 2 H H H H H H H OPh H 2 H H H H H H N(CH₂CH₂C(O)CH₃)₂H H 2 H H H H OH H OCH₃ H H 6 H H H H H OCH₃ OCH₃ OCH₃ H 2 H H H H OCH₃H OCH₃ OCH₃ H 6 H H H H H H H CH₃ H 2 H H H H H H N(CH₃)CH₂CH₂OH H H 2

and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates; the fluorescent dyes of formulae (X′) and (XI′):

wherein M′ represents an anionic counterion, derived from a salt of anorganic or mineral acid, or from an organic or mineral base that ensuresthe electrical neutrality of the dye; and R⁵ R⁷ R⁸ m H N(CH₂CH₂OH)₂ H 2H N(CH₂CH₂OH)₂ H 3 H N(CH₂CH₂OH)₂ H 4 H N(CH₂CH₂OH)₂ H 5 H N(CH₂CH₂OH)₂H 6 H N(CH₂CH₂OH)₂ H 8 H N(CH₂CH₂OH)₂ H 10 H N(CH₂CH₂OH)₂ H 12 HN(CH₂CH₂OH)₂ H 14 H N(CH₂CH₂OH)₂ H 16 H CH₃CH₂N(CH₂CH₂OH) H 2 HCH₃CH₂N(CH₂CH₂OH) H 4

and R⁵ R⁷ R⁸ m OCH₃ OCH₃ OCH₃  2 OCH₃ OCH₃ OCH₃  3 OCH₃ OCH₃ OCH₃  3OCH₃ OCH₃ OCH₃  4 OCH₃ OCH₃ OCH₃  5 OCH₃ OCH₃ OCH₃  8 OCH₃ OCH₃ OCH₃ 10OCH₃ OCH₃ OCH₃ 12 OCH₃ OCH₃ OCH₃ 14 OCH₃ OCH₃ OCH₃ 16

and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates; the fluorescent dyes of formula (XII) with: R¹ R² R³ R⁴ R⁵R⁶ R⁷ R⁸ R⁹ m H H H H H H OCH₃ OCH₃ OCH 2 H H H H OH OCH₃ H H H 2 H H HH H H H H H 2 H H H H H OCH₃ OCH₃ H H 2 H H H H OH H OH H H 6 H H H HOCH₃ H OCH₃ OCH₃ H 6 H H H H H H OH H H 6 H H H H OCH₃ H H H F 2 H H H HH H C(O)—OH H H 2 H H H H H H Isopropyl H H 2 H H H H H HN(CH₂CH₂C(O)CH₃)₂ H H 2 H H H H OH H OCH₃ H H 2 H H H H H H OH H H 2 H HH H H OCH₃ OH OH H 2 H H H H H CH₃ OCH₂Ph CH₃ H 2 H H H H H OCH₃ OCH₃OCH₃ H 2 H H H H H OCH₃ OCH₃ OCH₃ H 6 H H H H H H N(CH₃)₂ H H 6 H H H HH H OCH₃ OCH₃ OCH₃ 6 H H H H H H Phenyl H H 6 H H H H H OCH₃ OCH₃ H H 6H H H H H H C(O)—OH H H 6 H H H H H H N(n-Butyl)₂ H H 2 H H H H H H OCH₃OCH₃ H 3 H H H H H H OCH₃ OCH₃ H 2 H H H H H H OCH₃ OCH₃ H 5 H H H H H HOCH₃ H H 3 H H H H H H N(CH₃)₂ H H 3 H H H H H H H H H 3

and also the organic or mineral acid or base salts thereof, the opticalisomers, geometrical isomers and tautomers thereof, and the solvatesthereof such as hydrates; the fluorescent dyes of formula (XIII) with:R¹ R² R³ R⁴ R⁵ R⁶ R⁷ R⁸ R⁹ m CH₃ H H H OH H OCH₃ H H 2 CH₃ H H H H HOCH₃ OCH₂-Ph H 2 CH₃ H H H H H H H OCH₃ 2 CH₃ H H H F H H H H 2 CH₃ H HH H H H OPh H 2 CH₃ H H H H H N(CH₂CH₂OAc)₂ H H 2 CH₃ H H H OCH₃ H OCH₃OCH₃ H 2 CH₃ H H H H H H CH₃ H 2 CH₃ H H H H H OH H H 2 CH₃ H H H H OCH₃OCH₃ OCH₃ H 2 CH₃ H H H H OCH₃ OH OH H 2 CH₃ H H H H H OCH₃ OCH₃ OCH₃ 2CH₃ H H H H H H OCH₃ OH 2 CH₃ H H H H H N(n-butyl)₂ H H 2 CH₃ H H H HOCH₃ OCH₃ H H 2 CH₃ H H H H H H H H 2 CH₃ H H H H H i-propyl H H 2 H H HH H H OH H H 6 H H H H H OCH₃ OCH₃ OCH₃ H 6 H H H H OH H OCH₃ H H 2 H HH H OCH₃ H H OCH₃ OCH₃ 2 H H H H H H H H Br 2 H H H H H H OH H H 2 H H HH H H N(CH₃)₂ H H 6 H H H H OCH₃ OCH₃ OCH₃ H H 6 H H H H OH OCH₃ H H H 6H H H H H OCH₃ OCH₃ H H 6 H H H H H OCH₃ OCH₃ H H 2 H H H H H H C(O)—OHH H 6 H H H H H H C(O)—OH H H 2 H H H H H H i-propyl H H 2 H H H H H HN(CH₃)CH₂CH₂CN H H 2 H H H H H H OCH₃ OCH₂Ph H 2 H H H H H H H OPh H 2 HH H H H H N(CH₂CH₂C(O)CH₃)₂ H H 2 H H H H OH H OCH₃ H H 6 H H H H H OCH₃OCH₃ OCH₃ H 2 H H H H OCH₃ H OCH₃ OCH₃ H 6 H H H H H H H CH₃ H 2 H H H HH H N(CH₃)CH₂CH₂OH H H 2 CH₃ H H H H H N(CH₃)₂ H H 2

and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates; and the fluorescent dyes of formulae (XII′) and (XIII′)below:

with: R⁵ R⁷ R⁸ m H N(CH₂CH₂OH)₂ H  2 H N(CH₂CH₂OH)₂ H  3 H N(CH₂CH₂OH)₂H  4 H N(CH₂CH₂OH)₂ H  5 H N(CH₂CH₂OH)₂ H  6 H N(CH₂CH₂OH)₂ H  8 HN(CH₂CH₂OH)₂ H 10 H N(CH₂CH₂OH)₂ H 12 H N(CH₂CH₂OH)₂ H 14 H N(CH₂CH₂OH)₂H 16

R⁵ R⁷ R⁸ m OCH₃ OCH₃ OCH₃ 2 OCH₃ OCH₃ OCH₃ 3 OCH₃ OCH₃ OCH₃ 3 OCH₃ OCH₃OCH₃ 4 OCH₃ OCH₃ OCH₃ 5 OCH₃ OCH₃ OCH₃ 8 OCH₃ OCH₃ OCH₃ 10 OCH₃ OCH₃OCH₃ 12 OCH₃ OCH₃ OCH₃ 14 OCH₃ OCH₃ OCH₃ 16

and and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates; and preferably, the fluorescent dye(s) (b) are chosen fromthe following compounds:

and also the organic or mineral acid or base salts thereof, thegeometrical isomers and tautomers thereof, and the solvates thereof suchas hydrates; wherein M′ represents an anionic counterion, derived from asalt of an organic or mineral acid, or from an organic or mineral basethat ensures the electrical neutrality of the dye; and Q⁺ represents acationic counterion such as an alkali metal or alkaline-earth metal, itbeing understood that when the dye comprises an alkoxide group, then M′and Q⁺ may be absent to ensure the electrical neutrality of said dye.18. Process according to claim 1, characterized in that it alsocomprises the application to said keratin fibres of one or more reducingagents, preferably chosen from i) the reducing agents of formula (XVI)below, and also the addition salts thereof, and mixtures thereof:H(X)_(q)(R₁₀)_(t)  (XVI) in which formula (XVI): X represents P, S orSO₂, q represents an integer equal to 0 or 1, t represents an integerequal to 1 or 2, and R represents a linear or branched, saturated orunsaturated C₁ to C₂₀ alkyl radical, optionally interrupted with aheteroatom, and/or optionally substituted with one or more radicalschosen from hydroxyl, halo, amine, carboxyl, ((C₁-C₃₀)alkoxy)carbonyl,amido, ((C₁-C₃₀)alkyl)aminocarbonyl, ((C₁-C₃₀)acyl)amino, mono ordialkylamino, and mono or dihydroxylamino radicals; ii) thioglycolicacid, iii) thiolactic acid, iv) glyceryl monothioglycolate, v)cysteamine, vi) N-acetylcysteamine, vii) N-propionylcysteamine, viii)cysteine, ix) N-acetylcysteine, x) thiomalic acid, xi) pantetheine, xii)2,3-dimercaptosuccinic acid, xiii)N-(mercaptoalkyl)-o-hydroxyalkylamides, xiv) N-mono- orN,N-dialkylmercapto-4-butyramides, xv) aminomercaptoalkylamides, xvi)N-(mercaptoalkyl)succinamic acid derivatives, xvii)N-(mercaptoalkyl)succinimide derivatives, xviii) alkylaminomercaptoalkylamides, xix) the azeotropic mixture of 2-hydroxypropylthioglyconate and of (2-hydroxy-1-methyl)ethyl thioglycolate, xx)mercaptoalkylaminoamides, xxi) N-mercaptoalkylalkanediamides xxii)formamidinesulfinic acid derivatives, addition salts thereof, andmixtures thereof.
 19. Process according to claim 1, characterized inthat it does not use any reducing agent.
 20. Process according to claim1, characterized in that the triarylmethane dye(s) (a), and thefluorescent dye(s) (b), are applied together to the keratin fibres;preferably, the process comprises a step of applying to the keratinfibres a cosmetic composition which comprises one or more triarylmethanedyes (a) chosen from the compounds of formula (I), and also the opticalisomers thereof, the geometrical isomers thereof, the tautomers thereof,the organic or mineral acid or base salts thereof, the solvates thereofsuch as hydrates, and mixtures thereof, and one or more fluorescent dyes(b).
 21. Process according to claim 1, characterized in that itcomprises at least the following two successive steps: a first step ofapplying to said keratin fibres a cosmetic composition comprising one ormore fluorescent dyes (b), followed by, a second step of applying tosaid fibres a cosmetic composition comprising one or more triarylmethanedyes (a) chosen from the compounds of formula (I), and also the opticalisomers thereof, the geometrical isomers thereof, the tautomers thereof,the organic or mineral, acid or base salts thereof, the solvates thereofsuch as hydrates, and mixtures thereof.
 22. Process according to claim1, characterized in that it comprises at least the following twosuccessive steps: a first step of applying to said keratin fibres acosmetic composition comprising one or more triarylmethane dyes (a)chosen from the compounds of formula (I), and also the optical isomersthereof, the geometrical isomers thereof, the tautomers thereof, theorganic or mineral, acid or base salts thereof, the solvates thereofsuch as hydrates, and mixtures thereof, followed by a second step ofapplying to said fibres a cosmetic composition comprising one or morefluorescent dyes (b).
 23. Process according to claim 22, characterizedin that it comprises at least two successive steps in which the pH ofthe cosmetic composition(s) is between 6 and 11 inclusive, preferablybetween 7 and 10, more preferentially between 7.5 and 9.5 and betterstill between 9 and 9.5.
 24. Cosmetic composition comprising one or moretriarylmethane dyes (a) chosen from the compounds of formula (I), andalso the optical isomers thereof, the geometrical isomers thereof, thetautomers thereof, the organic or mineral acid or base salts thereof,the solvates thereof such as hydrates, and mixtures thereof, and one ormore fluorescent dyes (b), said composition optionally having a pH ofbetween 6 and 11 inclusive, preferably between 7 and 10, morepreferentially between 7.5 and 9.5 and better still between 9 and 9.5.25. Multi-compartment device comprising a first compartment containingone or more triarylmethane dyes (a) chosen from the compounds of formula(I), and also the optical isomers thereof, the geometrical isomersthereof, the tautomers thereof, the organic or mineral acid or basesalts thereof, the solvates thereof such as hydrates, and mixturesthereof, and a second compartment containing one or more fluorescentdyes (b).
 26. Use of one or more fluorescent dye(s) (b), combined withone or more triarylmethane dye(s) (a) chosen from the compounds offormula (I), and also the optical isomers thereof, the geometricalisomers thereof, the tautomers thereof, the organic or mineral acid orbase salts thereof, the solvates thereof such as hydrates, and mixturesthereof, for the dyeing of light keratin fibres, especially humankeratin fibres such as the hair, in chestnut-brown, dark chestnut-brown,brown, brown with a glint or even black, without using an additional dyeother than (a) or (b).